include the GPG wrapper from Lookout's Keyswap as test engine for gpgcli

In order to build up test cases for the gpgcli stuff, there needs to be a
wrapper for easily handling gpgcli from Java.  Lookout wrote a quick demo
app Keyswap that uses gpg --with-colons for getting data.

refs #2738
include test files from gnupg-for-android

#2738
don't set env vars in gpgcli wrapper, the aliases should handle that

As part of the test of the gpgcli aliases, they should work without any env
vars being set (e.g LD_LIBRARY_PATH or PATH).  Instead everything should be
properly setup in app_opt/aliases/common and app_opt/etc/environment.conf

#2738
include Apache Commons IO to simplify file operations
rename GPGCli tag from KeySwap to GPGCli for clarity when reading logcat
wire up AndroidTestCase infrastructure  #2738
add actual tests of importing public keys via gpgcli

#2738