create separate code paths for sp idle notification and mp idle notification

although atm they do the same thing

src/playmp_controller.cpp

@@ -549,3 +549,10 @@ bool playmp_controller::can_execute_command(const hotkey::hotkey_command& cmd, i
 	}
 	return res;
 }
+
+void playmp_controller::do_idle_notification()
+{
+	resources::screen->add_chat_message(time(NULL), "Wesnoth", 0, 
+		"This side is in an idle state. To proceed with the game, the host must assign it to another controller.",
+		events::chat_handler::MESSAGE_PUBLIC, false);	
+}

src/playmp_controller.hpp

@@ -58,6 +58,7 @@ protected:
 	virtual void after_human_turn();
 	virtual void finish_side_turn();
 	virtual void play_network_turn();
+	virtual void do_idle_notification();
 	void init_turn_data();
 
 	turn_info* turn_data_;

src/playsingle_controller.cpp

@@ -691,10 +691,7 @@ void playsingle_controller::play_side(const unsigned int side_number, bool save)
 		} else if(current_team().is_idle()) {
 			try{
 				end_turn_enable(false);
-				resources::screen->add_chat_message(time(NULL), "Wesnoth", 0, 
-					"This side is in an idle state. To proceed with the game, the host must assign it to another controller.",
-					events::chat_handler::MESSAGE_PUBLIC, false);
-
+				do_idle_notification();
 				before_human_turn(save);
 				while(1) {
 					play_idle_loop();
@@ -917,6 +914,16 @@ void playsingle_controller::play_ai_turn(){
 }
 
 
+/**
+ * Will handle sending a networked notification in descendent classes.
+ */
+void playsingle_controller::do_idle_notification()
+{
+	resources::screen->add_chat_message(time(NULL), "Wesnoth", 0, 
+		"This side is in an idle state. To proceed with the game, the host must assign it to another controller.",
+		events::chat_handler::MESSAGE_PUBLIC, false);
+}
+
 /**
  * Will handle networked turns in descendent classes.
  */

src/playsingle_controller.hpp

@@ -83,6 +83,7 @@ protected:
 	virtual hotkey::ACTION_STATE get_action_state(hotkey::HOTKEY_COMMAND command, int index) const;
 	void play_ai_turn();
 	void play_idle_loop();
+	virtual void do_idle_notification();
 	virtual void play_network_turn();
 	virtual void init_gui();
 	void check_time_over();