Added continuous charge mode + fixes

Added continuous charge mode for bosses to use, unlike the normal charge
it starts at 100% and uses up charge as it's used, it can be activated
at any time (if the boss behaviour allows it)

Renamed the Boss Fight Fortress behaviour forwards to sound less like
function names and more like messages (BFF_GetMaxHealthRequest,
BFF_OnTauntAbilityUsed, etc.)

Fixed weapon giving during spawn
Fixed wearables from the previous class persisting ( thanks to friagram:
https://forums.alliedmods.net/showpost.php?p=2080539&postcount=8 )

Ever so slightly more work on The Sorcerer