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.

srb2win_morehints.exe

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.)