Replace BridgeDB's use of python-gpgme with python-gnupg
Due to concerns which I've pointed out in #5463, we should assess the effort needed to replace BridgeDB's use of the python-gpgme module with python-gnupg (full disclosure: I wrote and maintain it). I'm recommending the one I maintain because I've auditted most of the GnuPG Python module/wrappers out there and they are all terrible. If someone else knows of another one which doesn't completely suck, feel free to use that instead.
Before starting work on this, someone should assess the effort required so that we can decide if it's worth it to go through with the switch.