refactor directives' controller instance creation to use js constructor

In your directives' controller, you were trying to import `ionic.controllers.?`'s behaviour by extending your `this` with their prototype, and `.call`ing their constructor with your `this`. 

Your end result can be accomplished much easier: you can create a normal instance of a `ionic.controllers.?` with the `new` operator, and at the end return it.

I refactored the directives' controller to be using the simpler `new` way :)