Add gamemode_query_status and teach gamemoded '-s'

This allows the client to query the daemon about the status of gamemode.

	Returns the following:
		 0 if gamemode is inactive
		 1 if gamemode is active
		 2 if gamemode is active and this client is registered
		-1 if the query failed

	Passing -s to gamemoded will simply query and print the current status.

	Allows for more comprehensive testing when using 'gamemoded -r' as well as more reactionary program behaviour

lib/client_impl.c

@@ -105,3 +105,9 @@ extern int real_gamemode_request_end(void)
 {
 	return gamemode_request("UnregisterGame");
 }
+
+// Wrapper to call UnregisterGame
+extern int real_gamemode_query_status(void)
+{
+	return gamemode_request("QueryStatus");
+}