Added Bootstrap List Group to the helper functions

Created helper functions for bootstrap functionalities - that would not need a widget. Complex helper functions like ```listGroup```, ```mediaList```, ```address```, ```blockquote``` are also included. Added documentation and examples for each function. List of bootstrap helper functions available:
1. icon
2. label
3. badge
4. listGroup
5. jumbotron
6. panel
7. pageHeader
8. well
9. media
10. mediaList
11. closeButton
12. caret
13. lead
14. abbr
15. blockquote
16. address
17. staticInput