fix(candyListController): fix slide index issue when using go to end

Details of other work done in this branch:
* Cleanup to pass lint test
* Push processTimeline into unit tested service
* Push displayPercentages into unit tested directive
* Added async third party lib help manage asynchonous code

Closes #9
Merge pull request #10 from ghachey/issue9

fix(candyListController): fix slide index issue when using go to end