hkp-source: when searching for keys, request the full fingerprint

This lets the user actually see the whole fingerprint in the 'Properties' subdialog
of the Remote Keys dialog, instead of just the key ID.

https://bugzilla.gnome.org/show_bug.cgi?id=719872

Signed-off-by: Stef Walter <stefw@gnome.org>
hkp-source: Prettify the downloaded fingerprint before setting it on the subkey

https://bugzilla.gnome.org/show_bug.cgi?id=719872

Signed-off-by: Stef Walter <stefw@gnome.org>