Use ng-submit directly, reduced watchers, using model controller's $validators

Enhancements & Improvements

1. Now, we don't have to use on-submit instead of ng-submit for form submission 😄
2. Using $validators available in ngModel controller instead of $parsers (now requires Angular >= 1.3.0)
3. Using formController's $submitted variable for maintaining form submission checks
4. Now, one can easily change form's state to submitted/pristine after form submission

Fixes

1. Injecting bs-validation directive on input elements with ng-model prefixed with data-

Code diff: v0.0.1...v0.0.2