diff --git a/package.json b/package.json
index 112f06e..9107f20 100644
--- a/package.json
+++ b/package.json
@@ -71,7 +71,7 @@
     "nodemon": "^1.11.0",
     "prettier": "^1.5.3",
     "semantic-release": "^8.0.3",
-    "supertest": "^3.0.0"
+    "supertest": "^4.0.0"
   },
   "jest": {
     "coverageReporters": [
diff --git a/yarn.lock b/yarn.lock
index 4a9ae81..48dd1af 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1275,6 +1275,13 @@ combined-stream@^1.0.5, combined-stream@~1.0.5:
   dependencies:
     delayed-stream "~1.0.0"
 
+combined-stream@^1.0.6:
+  version "1.0.7"
+  resolved "https://registry.yarnpkg.com/combined-stream/-/combined-stream-1.0.7.tgz#2d1d24317afb8abe95d6d2c0b07b57813539d828"
+  integrity sha512-brWl9y6vOB1xYPZcpZde3N9zDByXTosAeMDo4p1wzo6UMOX4vumB+TP1RZ76sfE6Md68Q0NJSrE/gbezd4Ul+w==
+  dependencies:
+    delayed-stream "~1.0.0"
+
 commander@^2.11.0, commander@^2.9.0:
   version "2.11.0"
   resolved "https://registry.yarnpkg.com/commander/-/commander-2.11.0.tgz#157152fd1e7a6c8d98a5b715cf376df928004563"
@@ -1419,9 +1426,10 @@ cookie@0.3.1:
   version "0.3.1"
   resolved "https://registry.yarnpkg.com/cookie/-/cookie-0.3.1.tgz#e7e0a1f9ef43b4c8ba925c5c5a96e806d16873bb"
 
-cookiejar@^2.1.0:
-  version "2.1.1"
-  resolved "https://registry.yarnpkg.com/cookiejar/-/cookiejar-2.1.1.tgz#41ad57b1b555951ec171412a81942b1e8200d34a"
+cookiejar@^2.1.2:
+  version "2.1.2"
+  resolved "https://registry.yarnpkg.com/cookiejar/-/cookiejar-2.1.2.tgz#dd8a235530752f988f9a0844f3fc589e3111125c"
+  integrity sha512-Mw+adcfzPxcPeI+0WlvRrr/3lGVO0bD75SxX6811cxSh1Wbxx7xZBGK1eVtDf6si8rg2lhnUjsVLMFMfbRIuwA==
 
 core-js@^2.4.0, core-js@^2.5.0:
   version "2.5.1"
@@ -1543,12 +1551,19 @@ debug@2, debug@2.6.9, debug@^2.2.0, debug@^2.6.3, debug@^2.6.8:
   dependencies:
     ms "2.0.0"
 
-debug@^3.0.1, debug@^3.1.0:
+debug@^3.0.1:
   version "3.1.0"
   resolved "https://registry.yarnpkg.com/debug/-/debug-3.1.0.tgz#5bb5a0672628b64149566ba16819e61518c67261"
   dependencies:
     ms "2.0.0"
 
+debug@^4.1.0:
+  version "4.1.1"
+  resolved "https://registry.yarnpkg.com/debug/-/debug-4.1.1.tgz#3b72260255109c6b589cee050f1d516139664791"
+  integrity sha512-pYAIzeRo8J6KPEaJ0VWOh5Pzkbw/RetuzehGM7QRRX5he4fPHx2rdKMB256ehJCkX+XRQm16eZLqLNS8RSZXZw==
+  dependencies:
+    ms "^2.1.1"
+
 decamelize@^1.0.0, decamelize@^1.1.1, decamelize@^1.1.2:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/decamelize/-/decamelize-1.2.0.tgz#f6534d15148269b20352e7bee26f501f9a191290"
@@ -1956,7 +1971,7 @@ express@^4.15.4:
     utils-merge "1.0.1"
     vary "~1.1.2"
 
-extend@3, extend@^3.0.0, extend@~3.0.0, extend@~3.0.1:
+extend@3, extend@~3.0.0, extend@~3.0.1:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/extend/-/extend-3.0.1.tgz#a755ea7bc1adfcc5a31ce7e762dbaadc5e636444"
 
@@ -2089,12 +2104,13 @@ forever-agent@~0.6.1:
   version "0.6.1"
   resolved "https://registry.yarnpkg.com/forever-agent/-/forever-agent-0.6.1.tgz#fbc71f0c41adeb37f96c577ad1ed42d8fdacca91"
 
-form-data@^2.3.1, form-data@~2.3.1:
-  version "2.3.1"
-  resolved "https://registry.yarnpkg.com/form-data/-/form-data-2.3.1.tgz#6fb94fbd71885306d73d15cc497fe4cc4ecd44bf"
+form-data@^2.3.3:
+  version "2.3.3"
+  resolved "https://registry.yarnpkg.com/form-data/-/form-data-2.3.3.tgz#dcce52c05f644f298c6a7ab936bd724ceffbf3a6"
+  integrity sha512-1lLKB2Mu3aGP1Q/2eCOx0fNbRMe7XdwktwOruhfqqd0rIJWwN4Dh+E3hrPSlDCXnSR7UtZ1N38rVXm+6+MEhJQ==
   dependencies:
     asynckit "^0.4.0"
-    combined-stream "^1.0.5"
+    combined-stream "^1.0.6"
     mime-types "^2.1.12"
 
 form-data@~1.0.0-rc4:
@@ -2113,9 +2129,18 @@ form-data@~2.1.1:
     combined-stream "^1.0.5"
     mime-types "^2.1.12"
 
-formidable@^1.1.1:
-  version "1.1.1"
-  resolved "https://registry.yarnpkg.com/formidable/-/formidable-1.1.1.tgz#96b8886f7c3c3508b932d6bd70c4d3a88f35f1a9"
+form-data@~2.3.1:
+  version "2.3.1"
+  resolved "https://registry.yarnpkg.com/form-data/-/form-data-2.3.1.tgz#6fb94fbd71885306d73d15cc497fe4cc4ecd44bf"
+  dependencies:
+    asynckit "^0.4.0"
+    combined-stream "^1.0.5"
+    mime-types "^2.1.12"
+
+formidable@^1.2.0:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/formidable/-/formidable-1.2.1.tgz#70fb7ca0290ee6ff961090415f4b3df3d2082659"
+  integrity sha512-Fs9VRguL0gqGHkXS5GQiMCr1VhZBxz0JnJs4JmMp/2jL18Fmbzvv7vOFRU+U8TBkHEE/CX1qDXzJplVULgsLeg==
 
 forwarded@~0.1.2:
   version "0.1.2"
@@ -3486,7 +3511,7 @@ merge@^1.1.3:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/merge/-/merge-1.2.0.tgz#7531e39d4949c281a66b8c5a6e0265e8b05894da"
 
-methods@^1.1.1, methods@~1.1.2:
+methods@^1.1.1, methods@^1.1.2, methods@~1.1.2:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/methods/-/methods-1.1.2.tgz#5529a4d67654134edcc5266656835b0f851afcee"
 
@@ -3522,10 +3547,15 @@ mime-types@^2.1.11, mime-types@^2.1.12, mime-types@~2.1.15, mime-types@~2.1.16,
   dependencies:
     mime-db "~1.30.0"
 
-mime@1.4.1, mime@^1.2.11, mime@^1.4.1:
+mime@1.4.1, mime@^1.2.11:
   version "1.4.1"
   resolved "https://registry.yarnpkg.com/mime/-/mime-1.4.1.tgz#121f9ebc49e3766f311a76e1fa1c8003c4b03aa6"
 
+mime@^2.4.0:
+  version "2.4.0"
+  resolved "https://registry.yarnpkg.com/mime/-/mime-2.4.0.tgz#e051fd881358585f3279df333fe694da0bcffdd6"
+  integrity sha512-ikBcWwyqXQSHKtciCcctu9YfPbFYZ4+gbHEmE0Q8jzcTYQg5dHCr3g2wwAZjPoJfQVXZq6KXAjpXOTf5/cjT7w==
+
 mimic-fn@^1.0.0:
   version "1.1.0"
   resolved "https://registry.yarnpkg.com/mimic-fn/-/mimic-fn-1.1.0.tgz#e667783d92e89dbd342818b5230b9d62a672ad18"
@@ -3564,6 +3594,11 @@ ms@2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/ms/-/ms-2.0.0.tgz#5608aeadfc00be6c2901df5f9861788de0d597c8"
 
+ms@^2.1.1:
+  version "2.1.1"
+  resolved "https://registry.yarnpkg.com/ms/-/ms-2.1.1.tgz#30a5864eb3ebb0a66f2ebe6d727af06a09d86e0a"
+  integrity sha512-tgp+dl5cGk28utYktBsrFqA7HKgrhgPsg6Z/EfhWI4gl1Hwq8B/GmY/0oXZ6nF8hDVesS/FpnYaD/kOWhYQvyg==
+
 mute-stream@0.0.7:
   version "0.0.7"
   resolved "https://registry.yarnpkg.com/mute-stream/-/mute-stream-0.0.7.tgz#3075ce93bc21b8fab43e1bc4da7e8115ed1e7bab"
@@ -4069,10 +4104,15 @@ q@^1.4.1:
   version "1.5.0"
   resolved "https://registry.yarnpkg.com/q/-/q-1.5.0.tgz#dd01bac9d06d30e6f219aecb8253ee9ebdc308f1"
 
-qs@6.5.1, qs@^6.5.1, qs@~6.5.1:
+qs@6.5.1, qs@~6.5.1:
   version "6.5.1"
   resolved "https://registry.yarnpkg.com/qs/-/qs-6.5.1.tgz#349cdf6eef89ec45c12d7d5eb3fc0c870343a6d8"
 
+qs@^6.6.0:
+  version "6.6.0"
+  resolved "https://registry.yarnpkg.com/qs/-/qs-6.6.0.tgz#a99c0f69a8d26bf7ef012f871cdabb0aee4424c2"
+  integrity sha512-KIJqT9jQJDQx5h5uAVPimw6yVg2SekOKu959OCtktD3FjzbpvaPr8i4zzg07DOMz+igA4W/aNM7OV8H37pFYfA==
+
 qs@~6.2.0:
   version "6.2.3"
   resolved "https://registry.yarnpkg.com/qs/-/qs-6.2.3.tgz#1cfcb25c10a9b2b483053ff39f5dfc9233908cfe"
@@ -4140,7 +4180,7 @@ read-pkg@^2.0.0:
     normalize-package-data "^2.3.2"
     path-type "^2.0.0"
 
-readable-stream@^2.0.2, readable-stream@^2.0.5, readable-stream@^2.0.6, readable-stream@^2.1.4, readable-stream@^2.1.5, readable-stream@^2.2.2:
+readable-stream@^2.0.2, readable-stream@^2.0.6, readable-stream@^2.1.4, readable-stream@^2.1.5, readable-stream@^2.2.2:
   version "2.3.3"
   resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-2.3.3.tgz#368f2512d79f9d46fdfc71349ae7878bbc1eb95c"
   dependencies:
@@ -4152,6 +4192,15 @@ readable-stream@^2.0.2, readable-stream@^2.0.5, readable-stream@^2.0.6, readable
     string_decoder "~1.0.3"
     util-deprecate "~1.0.1"
 
+readable-stream@^3.0.6:
+  version "3.2.0"
+  resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-3.2.0.tgz#de17f229864c120a9f56945756e4f32c4045245d"
+  integrity sha512-RV20kLjdmpZuTF1INEb9IA3L68Nmi+Ri7ppZqo78wj//Pn62fCoJyV9zalccNzDD/OuJpMG4f+pfMl8+L6QdGw==
+  dependencies:
+    inherits "^2.0.3"
+    string_decoder "^1.1.1"
+    util-deprecate "^1.0.1"
+
 readable-stream@~2.0.5:
   version "2.0.6"
   resolved "https://registry.yarnpkg.com/readable-stream/-/readable-stream-2.0.6.tgz#8f90341e68a53ccc928788dacfcd11b36eb9b78e"
@@ -4716,6 +4765,13 @@ string-width@^2.0.0, string-width@^2.1.0, string-width@^2.1.1:
     is-fullwidth-code-point "^2.0.0"
     strip-ansi "^4.0.0"
 
+string_decoder@^1.1.1:
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-1.2.0.tgz#fe86e738b19544afe70469243b2a1ee9240eae8d"
+  integrity sha512-6YqyX6ZWEYguAxgZzHGL7SsCeGx3V2TtOTqZz1xSTSWnqsbWwbptafNyvf/ACquZUXV3DANr5BDIwNYe1mN42w==
+  dependencies:
+    safe-buffer "~5.1.0"
+
 string_decoder@~0.10.x:
   version "0.10.31"
   resolved "https://registry.yarnpkg.com/string_decoder/-/string_decoder-0.10.31.tgz#62e203bc41766c6c28c9fc84301dab1c5310fa94"
@@ -4770,27 +4826,28 @@ strip-json-comments@~2.0.1:
   version "2.0.1"
   resolved "https://registry.yarnpkg.com/strip-json-comments/-/strip-json-comments-2.0.1.tgz#3c531942e908c2697c0ec344858c286c7ca0a60a"
 
-superagent@^3.0.0:
-  version "3.6.3"
-  resolved "https://registry.yarnpkg.com/superagent/-/superagent-3.6.3.tgz#eb95fcb576a9d23a730a9d0789731b5379a36cdc"
+superagent@^4.1.0:
+  version "4.1.0"
+  resolved "https://registry.yarnpkg.com/superagent/-/superagent-4.1.0.tgz#c465c2de41df2b8d05c165cbe403e280790cdfd5"
+  integrity sha512-FT3QLMasz0YyCd4uIi5HNe+3t/onxMyEho7C3PSqmti3Twgy2rXT4fmkTz6wRL6bTF4uzPcfkUCa8u4JWHw8Ag==
   dependencies:
     component-emitter "^1.2.0"
-    cookiejar "^2.1.0"
-    debug "^3.1.0"
-    extend "^3.0.0"
-    form-data "^2.3.1"
-    formidable "^1.1.1"
+    cookiejar "^2.1.2"
+    debug "^4.1.0"
+    form-data "^2.3.3"
+    formidable "^1.2.0"
     methods "^1.1.1"
-    mime "^1.4.1"
-    qs "^6.5.1"
-    readable-stream "^2.0.5"
+    mime "^2.4.0"
+    qs "^6.6.0"
+    readable-stream "^3.0.6"
 
-supertest@^3.0.0:
-  version "3.0.0"
-  resolved "https://registry.yarnpkg.com/supertest/-/supertest-3.0.0.tgz#8d4bb68fd1830ee07033b1c5a5a9a4021c965296"
+supertest@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/supertest/-/supertest-4.0.0.tgz#1fda3a5faf331b20ad5fb836ddf789e80b365db6"
+  integrity sha512-e3UaSMkmVaPQ10MHqb5T9G1mb3L6MVUtLTxkVhKWndHfXyZylwtkjWXD9FzyHqlZ1/EPfeTJ+QDtmax5fb02cw==
   dependencies:
-    methods "~1.1.2"
-    superagent "^3.0.0"
+    methods "^1.1.2"
+    superagent "^4.1.0"
 
 supports-color@^2.0.0:
   version "2.0.0"
@@ -5067,7 +5124,7 @@ user-home@^1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/user-home/-/user-home-1.1.1.tgz#2b5be23a32b63a7c9deb8d0f28d485724a3df190"
 
-util-deprecate@~1.0.1:
+util-deprecate@^1.0.1, util-deprecate@~1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/util-deprecate/-/util-deprecate-1.0.2.tgz#450d4dc9fa70de732762fbd2d4a28981419a0ccf"