Add confidence modifiers for type and time and add support for a player count modifier.

New CVars with their default values:
	g_confidenceRewardDoubleTime (30)
	g_confidenceBaseMod          (1.0)
	g_confidenceKillMod          (1.0)
	g_confidenceBuildMod         (0.6)
	g_confidenceDeconMod         (1.0)
	g_confidenceDestroyMod       (1.0)