s/workerGroup/eventLoopGroup/
Added docs for the waitForPendingOperationsToFinish method.
Fixed some questionable connection bookkeeping.
Merge branch 'threadless_connections' into connection_failure_listener

Conflicts:
	src/main/java/com/relayrides/pushy/apns/PushManager.java
	src/test/java/com/relayrides/pushy/apns/PushManagerTest.java
Merge branch 'connection_failure_listener' into drain_retry_queue_before_shutdown_take2

Conflicts:
	src/main/java/com/relayrides/pushy/apns/PushManager.java
Further bookkeeping fixes: make sure to set the initial count to a reasonable value (oops) and don't double-count connection closure (double-oops).
Moved counter management into dedicated methods for clarity. Fixed another double-counting problem.
Merge branch 'threadless_connections' into connection_failure_listener
Avoided double-reporting of connection closure/failure. Clarified docs and added tests.
Minor: removed a superfluous `throws` declaration.
Merge branch 'threadless_connections' into connection_failure_listener

Conflicts:
	src/main/java/com/relayrides/pushy/apns/PushManager.java
Merge branch 'connection_failure_listener' into drain_retry_queue_before_shutdown_take2

Conflicts:
	src/main/java/com/relayrides/pushy/apns/PushManager.java
Fixed some drain-before-shutdown logic that broke due to the active connection counting changes.