Symlink files to apg
Rename sufficientlysecure.keychain to thialfihar.android.apg
Change some classes from Keychain* to Apg*
Rename classes of renamed files
Adjust gradle environment

Using libs instead of libraries in preparation of including more
submodules.
Change more things back to APG
Add APG icon again, change theme a bit
Adjust about and changelog texts
Add checkstyle configuration

Run "tools/checkstyle".
Rename "pass phrase" and "armour"
Change "OpenPGP Keychain" to "APG"
Adjust CHANGELOG, remove DESCRIPTION

The README will serve as a description.
Adjust icon, resized via aaresize
Move some classes to pgp
Rename packages and classes of moved files
Reorder imports to conform to checkstyle config
Add forgotten break
Adjust variable/method naming to conform to style guide
Conform to style guide
Update copyright span for Thialfihar