|level_gained||level_gained: Gives skill levelup messages to the user|
|level_lost||level_lost: See level_gained, same idea but fires on skill level-down|
level_gained: Gives skill levelup messages to the user
Only fires if the xp gain isn't silent, so only really useful for messages. Arguments:
- mind - The mind that you'll want to send messages
- new_level - The newly gained level. Can check the actual level to give different messages at different levels, see defines in skills.dm
- old_level - Similar to the above, but the level you had before levelling up.
level_lost: See level_gained, same idea but fires on skill level-down