GPG agent use_agent gpg.conf setting

[Stef Walter <stef-list memberwebs com>]

Unlike openssh, gnupg needs a certain setting enabled in gpg.conf in
order for gpg to use the agent.

Previously we've set this from a UI in the seahorse-preferences. The
gpg.conf file was edited by the UI and this line was added or commented out.

Is this still a good approach, now that the GPG agent is in
gnome-keyring? So far there hasn't really been any preferences UI for
gnome-keyring. But perhaps that needs to change and we need to have a
concept for a common crypto preference UI.

People have complained in the past that there's two menu items for a
password manager and the preferences 'capplet'. Is there a good way to
combine these?

Sadly the UI freeze has already come and gone for this release. Although
I would think that keeping the old UI in seahorse for this preference
would qualify as 'freeze'.

I guess keeping the old UI is our only option for now, unless we somehow
make editing of gpg.conf automatic, but I can't see that turning out well.

Cheers,

Stef