Implement the close and revert menu choices, as well as PC editor help

- Fix storing directions in save file as control characters

src/scenedit/scen.actions.cpp

@@ -2058,6 +2058,8 @@ void town_entry(location spot_hit) {
 // is slot >= 0, force that slot
 // if -1, use 1st free slot
 void set_up_start_screen() {
+	reset_lb();
+	reset_rb();
 	set_lb(0,LB_TITLE,LB_NO_ACTION,"Blades of Exile");
 	set_lb(1,LB_TITLE,LB_NO_ACTION,"Scenario Editor");
 	set_lb(3,LB_TEXT,LB_NEW_SCEN,"Make New Scenario");

src/scenedit/scen.main.cpp

@@ -193,7 +193,11 @@ void handle_menu_choice(eMenu item_hit) {
 		case eMenu::FILE_OPEN:
 			if(change_made && !save_check("save-before-load"))
 				break;
-			file_to_load = nav_get_scenario();
+		if(false)
+		case eMenu::FILE_REVERT:
+			if(change_made && cChoiceDlog("save-before-revert", {"revert", "cancel"}).show() == "cancel")
+				break;
+			file_to_load = item_hit == eMenu::FILE_OPEN ? nav_get_scenario() : scenario.scen_file;
 			if(!file_to_load.empty() && load_scenario(file_to_load, scenario)) {
 				cur_town = scenario.last_town_edited;
 				town = scenario.towns[cur_town];
@@ -214,6 +218,12 @@ void handle_menu_choice(eMenu item_hit) {
 				set_up_main_screen();
 			}
 			break;
+		case eMenu::FILE_CLOSE:
+			if(!save_check("save-before-close"))
+				break;
+			overall_mode = MODE_INTRO_SCREEN;
+			set_up_start_screen();
+			break;
 		case eMenu::QUIT: // quit
 			if(!save_check("save-before-quit"))
 				break;