Use 24h format for times in messages

Currently we leave that out, making it unclear whether it's a.m./p.m.

changed milestone to %GTK Next

added T: bug label

changed title from Add a.m./p.m. indicators to time to Use 24h format for times in messages

Fixed by @grote in 48780909.

closed

changed milestone to %GTK 0.1.0-beta1