Error out if Vala < 0.13.2, GTK+ 3 and extensions
Error out if Vala < 0.13.2, GTK+ 3 and extensions

See https://bugs.launchpad.net/midori/+bug/871579


dokidokivisual/midori,dokidokivisual/midori,dokidokivisual/midori,dokidokivisual/midori,dokidokivisual/midori