mint-arena: Rename cl_localClients cvar to cl_localPlayers

Considered an API break, so API version was increased.
mint-arena: Make it easier to change VM prefix
mint-arena: Remove unused ForceClientSkin code
Merge remote-tracking branch 'mint-arena/master'
mint-arena: Remove unused function ClientSkin
mint-arena: Add more optional bubble effects

Set cg_oldBubbles 0 to enable new bubble effects

- Make projectile bubble trails more faster to surface and last longer.
- Add bubble breath puffs (based on Team Arena cold breath puffs).
- Add bubbles to gib effect when it player is underwater.

The first two are based on Turtle Arena, though I made bubbles rise faster.
ebx: Remove "IOQ3ZTM // BUBBLES" code, to be replaced

I merged the "#ifdef IOQ3ZTM // BUBBLES" code into mint-arena, with some changes.
The easiest way to merge it in is to remove the existing code probably.
Merge remote-tracking branch 'mint-arena/master'

Conflicts:
	code/cgame/cg_effects.c
	code/cgame/cg_local.h
	code/cgame/cg_main.c
	code/cgame/cg_players.c
mint-arena: Fix bubble origins for trace in CG_BubbleThink
Merge remote-tracking branch 'mint-arena/master'
ebx: Enable new bubble effects by default