[CamelGPGContext] Prefer gpg2 over gpg
[CamelGPGContext] Prefer gpg2 over gpg

If there is a newer version installed, then use it, rather than
the old.

tintou/evolution-data-server,matzipan/evolution-data-server,tintou/evolution-data-server,tintou/evolution-data-server,matzipan/evolution-data-server,matzipan/evolution-data-server,matzipan/evolution-data-server,tintou/evolution-data-server,matzipan/evolution-data-server