Add set_angle 'immediate' parameter. (#357)

* Add set_angle 'immediate' parameter.
Modified fade_in transition to happen between :setup and :ready so that :ready don't start before fade_in is finished.

* docs: Automatic update of API docs

* Same fixes in style and removed a useless test.

Co-authored-by: StraToN <StraToN@users.noreply.github.com>

addons/escoria-core/game/scenes/transitions/transition.gd

@@ -2,7 +2,7 @@
 extends ColorRect
 
 
-# Emitted when the transition was player
+# Emitted when the transition was played
 signal transition_done