Update SpiderMonkey binaries

[progval]

An issue in SpiderMonkey prevented me from running the test262 suite: the output of JSON.stringify just stopped on some unicode characters (which the JSON parser complained about):

vlorentz@gommier:~/js/LambdaS5/tests$ cat /tmp/bar.js 
var hanidec_numbers = "〇一二三四五六七八九";
vlorentz@gommier:~/js/LambdaS5/tests$ ../bin/js --help
[…]
Version: JavaScript-C 1.8.5+ 2011-04-16
[…]
vlorentz@gommier:~/js/LambdaS5/tests$ ../bin/js -e "print(JSON.stringify(Reflect.parse(read('/tmp/bar.js'))))"
{"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":35},"source":null},"type":"Program","body":[{"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":34},"source":null},"type":"VariableDeclaration","kind":"var","declarations":[{"loc":{"start":{"line":1,"column":4},"end":{"line":1,"column":34},"source":null},"type":"VariableDeclarator","id":{"loc":{"start":{"line":1,"column":4},"end":{"line":1,"column":34},"source":null},"type":"Identifier","name":"hanidec_numbers"},"init":{"loc":{"start":{"line":1,"column":22},"end":{"line":1,"column":34},"source":null},"type":"Literal","value":"

This bug has been fixed in the current version of SpiderMonkey. I also had to update a part of of js/spiderMonkey.ml as SpiderMonkey now supports only one handler in try…catch blocks.

I also updated the symlink bin/js to the newest x86_64 version (the i686 version no longer works on x86_64 architecture because of .so handling)

(PS: For some reason, GitHub wants to merge commits Fix test case tests/unit-tests/regexp-exec.js and Move forgotten file., while you already merged them)

[progval]

Oh, and this patch also fixes #25.