Add new abstract class to listen notification.

To get notification for voting, new abstract class is added.
Other plugin developer can listen notification by extending
this class.
Implement new method call to notifier
Add new abstract class to listen notification.

To get notification for voting, new abstract class is added.
Other plugin developer can listen notification by extending
this class.
Implement new method call to notifier
Change class name and fix copyright
Add test for GerritTriggeredBuildListener
Merge branch 'event-handler3' of https://github.com/rinrinne/gerrit-trigger-plugin into event-handler3

Conflicts:
	gerrithudsontrigger/src/main/java/com/sonyericsson/hudson/plugins/gerrit/trigger/gerritnotifier/GerritNotifier.java
Fix missed confliction
Extract zip resource then update gerrit command for review
Remove unnecessary file
Merge pull request #90 from rinrinne/event-handler3

Add new abstract class to listen notification for voting