fixes #TC-2779: multiple widgets won't build in the same app

Since the resolution of [ALOY-659](https://jira.appcelerator.org/browse/ALOY-659) through [this commit](https://github.com/appcelerator/alloy/commit/76f34fec73476426f49b423de8f31b6a1bf45e66) there's a bug when tracking the files already compiled to `Resources`. Controllers or views for which another file with the same path (but in an other directory) exist are simply ignored.

This is obviously the case with widgets's `widget.js` files. Say we have two widgets:

 * app/widgets/firstWidget/controllers/widget.js
 * app/widgets/anOtherWidget/controllers/widget.js

Both of these widgets will be added in the tracker collection with the key "`widget`", resulting with only the first loaded widget.js file being handheld by alloy.

The associated Jira issue is https://jira.appcelerator.org/browse/TC-2779