Make karma toggleable

Add in feedback message

Update client defines.dm

keep it as bool I guess

Update karma.dm

Make it persistent

Update karma.dm

Update karma.dm

Update preferences.dm

make it compile, include kyet's suggestions

fix some things with the help of dtx

code/modules/karma/karma.dm

@@ -85,6 +85,9 @@ var/list/karma_spenders = list()
 		log_game("Illegal karma spending attempt detected from [key] to [M.key]. Using the same IP!")
 		to_chat(src, "<span class='warning'>You can't spend karma on someone connected from the same IP.</span>")
 		return FALSE
+	if(!M.client.wants_karma)
+		to_chat(src, "<span class='warning'>That player has turned off incoming karma.")
+		return FALSE
 	return TRUE