A little Script Creator work and little checks. (#9)

* No builds allowed here.

* Try something.

* Next work.

* Add some Logging stuff for testing purpose.

* Ok, this should log it priperly.

* Replace MainMenu with Screen Selection.

* Redo Screen Logic.

* Switch back to old MainMenu.

* Only access Scriptlist, when Scripts are found.

Hopefully avoid crashes with that.

* Remove unused String, because we use the MainMenu again.

source/screens/scriptlist.cpp

@@ -365,7 +365,7 @@ void ScriptList::ListSelection(u32 hDown, u32 hHeld) {
 
 	if (hDown & KEY_B) {
 		fileInfo.clear();
-		Gui::screenBack();
+		Screen::back();
 		return;
 	}