clean up PinEntryActivity's layout
move version stuff to GnuPrivacyGuard and eliminate GPGApplication

After reading about the android.app.Application class, its not really
intended to be a global state class.  It is meant to handle global state
changes, and has a specific API.  GnuPrivacyGuard.java is currently two
things combined: 1) the global app repo of variables, and 2) the test log
view.  The test log view should be split out of GnuPrivacyGuard.java.
when starting dirmngr/pinentry onBoot, also start gpg-agent
fix crash when displaying an empty key ring
stop pinentry from zombieing when the back button is pressed
REBAER     clean up PinEntryActivity's layout