refactor(rn-carousel): various improvements

Added features :
 - add rn-carousel-indicator option (fix #8)
 - add rn-carousel-index two way data binding to control and get the carousel index
 - added many e2e tests
 - removes the announcer/subscriber pattern and use instead a ngRepeat expression parser and watch the collection directly

BREAKING CHANGES: the carousel has been renamed to rn-carousel to prevent angularui bootstrap carousel collision (fix #3)