Update OsmDroid to 4.2

It has removed the "Safe" set of overlays, etc.
Move the clearing of cache to onDestroy() rather than onStop()

onStop() gets called too frequently for it to be wiping out caches.
Use GPS updates from service only, don't try to test MLS at the same time
Jump directly to the point if this is the first fix, otherwise animate over
Save zoom level on rotation
Save center of the map and restore when rotating
Changed Log Activity truncation, after 100 messages, start truncating
the messages. This way, there is detailed information at the start for
debugging.
Prefs not saving the nickname
Issue #684 prefs not saving nick
Merge pull request #686 from keverets/osmdroid-fixes

MapActivity fixes
Merge pull request #687 from garvankeeley/provider-to-client

Prefs not saving nickname