git-annex bundles gpg on OSX, but this bundled one is not integrated with
gpg-agent. So, if gpg is installed system-wide, it's probably better to use
that one (barring any versioning issues).

A solution might be to move the gpg binary to a different directory and put
it at the end of PATH, not the front. So system one is used if available.

This should also be considered for the linux standalone builds.

> [[done]] for both OSX and linux. --[[Joey]]