WarpEventBus observes Before event instead of LocalExecutionEvent.
Introduce (Start/Stop)EventBus events for WarpEventBus startup/shutdown.
This allows for observing and intercepting the process.
Functional test for WarpEventBus
Merge remote-tracking branch 'origin/ARQ-1027-1' into 1.0.0.Alpha4

Conflicts:
	impl/src/main/java/org/jboss/arquillian/warp/impl/client/eventbus/WarpEventBus.java