Allow for 10 emblem hints on a map by poking the drawer a bit.
Prepared for 2.2's release but didn't make feature freeze, has +3 in internal but obviously not just merging without public review now we've moved back here.
Test with the vanilla campaign (assuming emblem hints have been unlocked) to check that nothing has been modified there, then test with vsl_finaldemo-v1_0.pk3 to see a map with 10 emblem hints in action.
(The diff could technically have been net-compatible and therefore have gone into master, but I accidentially merged next and decided to roll with it.)