Fix setting g_gametype in arcade menu

g_gametype cvar isn't setup yet, so engine wasn't set it.
Use teampref in arcade menu

It's more reliable then wait and team command.
Use trap_Cvar_Set to set teampref in UI
Double com_zoneMegs, now it's 48 Megs

The entityState_t and playerState_t stored in client/server are in zone in Spearmint, so double the zone memory size.
Merge remote-tracking branch 'spearmint/master'

Conflicts:
	code/qcommon/common.c