move notifiation icon path to game_config

src/desktop/dbus_notification.cpp

@@ -145,7 +145,7 @@ uint32_t send_dbus_notification(DBusConnection *connection, uint32_t replaces_id
 			DBUS_TYPE_INVALID);
 	}
 
-	std::string app_icon_ = game_config::path + "images/game-icon.png";
+	std::string app_icon_ = game_config::path + game_config::images::app_icon;
 	LOG_DU << "app_icon_=\'" << app_icon_ << "\'\n";
 
 	const char *app_icon = app_icon_.c_str();

src/game_config.cpp

@@ -112,7 +112,9 @@ namespace game_config
 			wml_menu = "buttons/WML-custom.png",
 			level,
 			ellipsis,
-			missing;
+			missing,
+			// notifications icon
+			app_icon = "images/game-icon.png";
 	} //images
 
 	std::string shroud_prefix, fog_prefix;

src/game_config.hpp

@@ -111,7 +111,9 @@ namespace game_config
 			wml_menu,
 			level,
 			ellipsis,
-			missing;
+			missing,
+			// notifications icon
+			app_icon;
 	} //images