Using JSON.parse unconditionally when transforming response string

closes #55

lib/defaults.js

@@ -2,8 +2,6 @@
 
 var utils = require('./utils');
 
-var JSON_START = /^\s*(\[|\{[^\{])/;
-var JSON_END = /[\}\]]\s*$/;
 var PROTECTION_PREFIX = /^\)\]\}',?\n/;
 var DEFAULT_CONTENT_TYPE = {
   'Content-Type': 'application/x-www-form-urlencoded'
@@ -30,9 +28,9 @@ module.exports = {
   transformResponse: [function (data) {
     if (typeof data === 'string') {
       data = data.replace(PROTECTION_PREFIX, '');
-      if (JSON_START.test(data) && JSON_END.test(data)) {
+      try {
         data = JSON.parse(data);
-      }
+      } catch (e) {}
     }
     return data;
   }],