Update changelog and contributors.

changelog.md

+# v1.3.7 #
+- [BUG] fixed issue where multiple belongsTo or hasOne associations to the same table overwrite each other
+
 # v1.3.6 #
 - [BUG] don't update an existing updatedAt-attribute if timestamps option for a DAO is false
 

package.json

 {
   "name": "sequelize",
   "description": "MySQL ORM for Node.JS",
-  "version": "1.3.6",
+  "version": "1.3.7",
   "author": "Sascha Depold <sascha@depold.com>",
   "contributors": [
     { "name": "Sascha Depold", "email": "sascha@depold.com" },
-    { "name": "Meg Sharkey", "email": "meg@metamarkets.com" }
+    { "name": "Meg Sharkey", "email": "meg@metamarkets.com" },
+    { "name": "Chase Geigle", "email": "sky@skytrife.com" }
   ],
   "dependencies": {
     "mysql": "0.9.x",