-fix bug in cache for atlas import/export

-fix some menus
-fixed bug in out transition curves
-detect and remove file:/// in collada
-remove multiscript for now
-remove dependencies on mouse in OS, moved to Input
-avoid fscache from screwing up (fix might make it slower, but it works)
-funcref was missing, it's there now

core/os/os.cpp

@@ -430,7 +430,7 @@ Error OS::native_video_play(String p_path) {
 	return FAILED;
 };
 
-bool OS::native_video_is_playing() {
+bool OS::native_video_is_playing() const {
 
 	return false;
 };
@@ -447,6 +447,15 @@ void OS::set_mouse_mode(MouseMode p_mode) {
 
 }
 
+bool OS::can_use_threads() const {
+
+#ifdef NO_THREADS
+	return false;
+#else
+	return true;
+#endif
+}
+
 OS::MouseMode OS::get_mouse_mode() const{
 
 	return MOUSE_MODE_VISIBLE;