Increase the default 3D manipulator gizmo opacity for better visibility
Increase the default 3D manipulator gizmo opacity for better visibility

- Brighten gizmos when highlighted to make the difference between a
  non-highlighted and a highlighted gizmo more visible.
- Tweak the manipulator gizmo size property hint.

(cherry picked from commit 8522ac77113c3d5239ff4c6cd74ab7b92e1ee663)

ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot,ex/godot