fix(gradle): Option dependency resolution

Added JitPack, as com.gu.Option hasn't been updated in years, and they
never pushed to JCenter or any other repo, so I used JitPack.

Fix #88.

build.gradle

@@ -11,3 +11,12 @@ buildscript {
         classpath 'com.android.tools.build:gradle:2.3.0'
     }
 }
+
+subprojects {
+    repositories {
+        mavenCentral()
+        maven {
+            url 'https://jitpack.io/'
+        }
+    }
+}

library/build.gradle

@@ -11,15 +11,10 @@ buildscript {
     }
 }
 
-repositories {
-    mavenCentral()
-    maven { url 'http://guardian.github.com/maven/repo-releases' }
-}
-
 dependencies {
     compile 'com.android.support:appcompat-v7:25.3.1'
     compile 'com.android.support:support-annotations:25.3.1'
-    compile 'com.gu:option:1.3'
+    compile 'com.github.guardian:Option:e933c3a31d'
     compile 'com.github.frankiesardo:auto-parcel:0.3.1'
     compile 'com.google.auto.value:auto-value:1.1'
     annotationProcessor 'com.github.frankiesardo:auto-parcel-processor:0.3.1'

sample/build.gradle

@@ -1,10 +1,5 @@
 apply plugin: 'com.android.application'
 
-repositories {
-    mavenCentral()
-    maven { url 'http://guardian.github.com/maven/repo-releases' }
-}
-
 dependencies {
     compile project(':library')
 }