Fix certain Lua script errors hanging the GUI (#899)

* Fixed a bug where a standalone Lua script w/o a run function will hang the GUI on non-color radios

* Prevent Lua standalone window from opening if Lua failed on load

* Fixed scroll down key in TX12 simulator
Copied key definitions from TX16S

* Fixed the Lua error trying to call nil value when no scripts are loaded.

* I messed up in the previous commit; now it does not freeze and it does not call nil.

radio/src/gui/colorlcd/radio_sdmanager.cpp

@@ -334,8 +334,8 @@ void RadioSdManagerPage::build(FormWindow * window)
               std::string fullpath = currentPath + "/" + name;
               menu->addLine(STR_EXECUTE_FILE, [=]() {
                 luaExec(fullpath.c_str());
-                //TODO: check 'luaState'
-                StandaloneLuaWindow::instance()->attach(window);
+                if (luaState != INTERPRETER_RELOAD_PERMANENT_SCRIPTS)
+                  StandaloneLuaWindow::instance()->attach(window);
               });
             }
 #endif

radio/src/gui/colorlcd/radio_tools.cpp

@@ -126,8 +126,10 @@ void RadioToolsPage::rebuild(FormWindow * window)
               *((char *)getBasename(toolPath)-1) = '\0';
               f_chdir(toolPath);
 
-              StandaloneLuaWindow::instance()->attach(window);
               luaExec(path_str.c_str());
+              if (luaState != INTERPRETER_RELOAD_PERMANENT_SCRIPTS)
+                StandaloneLuaWindow::instance()->attach(window);
+              
               return 0;
             },
             OPAQUE);