Always try and order pages, catching HandshakeNotCompleteException as
necessary.

The previous code could crash if the handshake had completed at least
once in the activity's lifetime.

Rather than try and track the handshake status in the activity, catch
the exception and try again in onHandshakeCompleted.
Fix null pointer exceptions when updating the ongoing notification.

- Refactor the scrobbling code in to Scrobble.java.

- Check that objects are non-null before operating on them.
Remove duplicate entries from the release instructions.
Merge branch 'develop' into eventbus

# Conflicts:
#	Squeezer/src/main/java/uk/org/ngo/squeezer/framework/ItemListActivity.java
Include proguard-eventbus.cfg when building release targets.
Remove all sticky events when disconnecting from the Squeezeserver.