about: Fix the program's name in the title
Title currently says "About Glade". It's not a big deal because it's not
actually shown anywhere, but just for correctness let's change it to
"About Virt-Viewer".
Thanks Jonathon Jongsma for pointing this out.
Signed-off-by: Fabiano FidĂȘncio <fidencio@redhat.com>
Acked-by: Eduardo Lima (Etrunko) <etrunko@redhat.com>