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");