Update hubot to 3.0

package.json

@@ -14,7 +14,7 @@
   "dependencies": {
     "cheerio": "0.19.0",
     "coffee-script": "^1.9.2",
-    "hubot": "^2.12.0",
+    "hubot": "3.x",
     "hubot-auth": "^1.2.0",
     "hubot-help": "^0.1.1",
     "hubot-incoming-webhook": "^1.0.1",