Add .rvmrc for isolating CocoaPods version when working on TransitionKit
Bump Podfile.lock for CocoaPods 0.18.1
Reworked API slightly to avoid overlap with common event and state introspection methods when subclassing:

* `start` and `isStarted` have become `activate` and `isActive`
* `addEventsFromArray:` and `addStatesFromArray:` shortened to just `addEvents:` and `addStates:`
Bump Podspec to 1.1.0