Merging in EventsSpec, PublicMethodsSpec, and fixing slider source code

Hey seiyria,

After much delay, its finally here! Here are the changes included in this commit:

- Adding in the EventsSpec and PublicMethodsSpec
- Updating bootstrap-slider code to pass unit tests
- Refactoring public interface code of boostrap-slider
- Adding in code to ensure proper deletion/event unbinding when destroy() is called on slider

I ran the tests with 'grunt test' and everything appears to be working well!