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Changed behavior of 2D stabilization:
- Fixed epic spelling error.
- Neither 3d viewport nor MovieClip compositor input node
are using stable footage now.
- Now one thread lock can be avoided -- stable shot
isn't acquiring from several threads.
- Added compositor noe Distort->Stabilize 2D which is
supposed to stabilize "incoming" image using movie clip
block as reference.
Probably it could be useful to define MAT4 socket type and
use it in MovieClip node as output for stabilization and
as input socket for Stabilization node so relation could be
easily visible on "graph".