MPDroidService: If MPDroid task is swipped to remove, restart service.

This works around the default behaviour that if MPDroid is killed, the service
should be. Since, in this case, the service is a completely separate entity,
restart and get back to where it was on main process task swipe kill.
MPDroidService: More audio focus improvements.
MPDConnection: Reformat
MPDConnection: Make MPDCommandResult a nested class and cleanup warnings.
MPDConnection: Move classes used by MpdCallable exclusively to MpdCallable.
MPD.java: Move listallinfo/getHost/getPort into JMPDComm.
MPDConnection: Many warning fixes, tighten direct access.

This includes removing direct public access to anything in connection, anything
in here should be accessed elsewhere in JMPDComm.
MPDConnection: Refactor sendCommandQueue.
MPDConnection: Use a statically compiled pattern for line parsing.
MPDConnection: Fix exception warnings.
MPDConnection: Cleanup innerConnect().
MPDConnection: Remove unnecessary nested try/catch.
MPDConnection: connect() return value is discarded, change signature to void.

connect() MPD version return value is discarded and is stored as a field,
change the siguature to void.
MPDConnection: Remove confusing variable reuse.
MPDConnection: Cleanup command result processing.
MPDConnection: Make field returns and field parameter assignments immutable.
NowPlayingSmallFragment: Fix cover show failure.

From time to time NowPlayingSmallFragment cover will fail to show while
NowPlayingFragment never fails. The only difference between the cover download
is NowPlayingFragment uses the priority boolean (what does that even do?) so,
use it.
MPDConnection: Remove ping command construction from the loop.
MPDConnection*Socket: Clean up warnings.
MPDConnection: Refactor the isConnected() logic.

Before the isConnected() logic was slightly erratic, this is an attempt to make
it a little less erratic.