SceneMainLoop -> SceneTree

-=-=-=-=-=-=-=-=-=-=-=-=-=-

*YOUR SOURCE MIGHT NOT WORK*
For mor information on fix:
https://github.com/okamstudio/godot/wiki/devel_scene_tree

Other stuff:
-Shower of bullets demo
-Fixes all around

scene/gui/label.cpp

@@ -339,7 +339,7 @@ int Label::get_longest_line_width() const {
 
 int Label::get_line_count() const {
 
-	if (!is_inside_scene())
+	if (!is_inside_tree())
 		return 1;
 	if (word_cache_dirty)
 		const_cast<Label*>(this)->regenerate_word_cache();