Common directory for different installs of GnuPG

[Robert J. Hansen]

> I'd like to know if setting both versions to point at the same
> directory to obtain the pubring.gpg, secring.gpg and trustdb.gpg
> files can cause critical issues.

Unlikely.  It's technically possible to have configuration files that
don't work with 1.4 and 2.0/2.1, but it involves options you likely
shouldn't have set in the first place.