Changed the ParseAndEmit tests to compare parse event from the original file and the emitted file

* Also moved enumerable extensions to its own file and used more generic method names
Changed EmitterTests to use the Emit helper method in all test methods
Eased some complexity with parse events by introducing builder classes

* Renamed helper classes to reflect what they actually help with
Simplified creating events in the EmitterTests tests by using EventsHelper
Merge pull request #73 from rogernorling/emitter-tests-refactor-1

Changed ParseAndEmit to compare parse event sequences