deps: pin socket.io to 1.3.7 after they introduced a breaking change

Author: shakyShane

package.json

@@ -54,7 +54,7 @@
     "resp-modifier": "^5.0.0",
     "serve-index": "^1.7.0",
     "serve-static": "^1.10.0",
-    "socket.io": "^1.3.7",
+    "socket.io": "1.3.7",
     "ua-parser-js": "^0.7.9",
     "ucfirst": "^1.0.0"
   },