Use strict

Requires turning IrcUtils into an Angular service, because the global variable
trick won't work with use strict.
Reuse is still easily possible by removing the angular wrapping around it.

.jshintrc

@@ -1,8 +1,11 @@
 {
+  "browser": true,
+  "devel": true,
   "globals": {
     "angular": false,
-    "$": false,
-    "window": false,
-    "console": false
+    "weeChat": false,
+    "_": false,
+    "Notification": false,
+    "Favico": false
   }
 }