levelling doesn't trigger a refresh of known spells

[speedwaystar]

this occurs because the code no longer reinitializes itself every 3 seconds like it used to (!), but is now asynchronous and relies on OnEvent triggers. accordingly, we need to add an PLAYER_LEVEL_UP OnEvent call to SMARTBUFF_SetBuffs()

[ynazar1]

Note for later:

register event and add it to the if statement at around line 706 in smartbuff.lua