Blender Git Loki

Merge branch 'blender-v2.83-release'

Fix: Incorrect f-string in previews.py

Contributed by @deadpin

Differential Revision: https://developer.blender.org/D7458

Fix Linux/GCC build error after recent changes

UV: add Reset operator to menu in uv editor

Differential Revision: https://developer.blender.org/D7482

Strengthen modifiers test validation, from D7397.

Submitting on behalf of Jesse Y (deadpin).
In test harness for modifier testing, now run mesh validation
on output mesh. Also, fix printing so it interleaves properly.

Merge remote-tracking branch 'origin/blender-v2.83-release'

Fix T75472 Crash on "Remove Empty Animation Data" in NLA editor

The `ANIMFILTER_NODUPLIS` option, to prevent duplicates in the list of
animation data to be freed, was missing. This caused a use-after-free.

Merge branch 'blender-v2.83-release'

Fix clang-format differences between version 6 and 9

Version 6 does not appear to respect clang-format off for header sorting.

Cleanup: clang-format

Merge branch 'blender-v2.83-release'

Fix T75920: Add object - Align to 3D cursor not working.

3DCursor is UI data (hence not expected to be affected by undo) that is
stored in actual data (Scene)... So it needs some special care during
undo.

New undo code now re-reads data into existing memory, which means
copying of 3DCursor data has to happen earlier in that case, when we
still have both old and newly read data available.

Cleanup: Fix strict compiler warning

Libmv: Cleanup, spelling and naming in bundle adjustment

Just more things which were discovered to be annoying on unclear when
adding more features to this code.

Windows: Add sccache support.

sccache [1] is one of the few ccache like solutions that will
work on windows.

sccache support can be enabled with the `WITH_WINDOWS_SCCACHE`
cmake option however it will only will work with ninja as the
build system, msbuild is not supported currently.

Advanced option, developes are expected to obtain and configure
sccache on their own.

```
Full build no cache 1428.90s (100.00%)
Full build cached 434.34s ( 30.40%)
```

[1] https://github.com/mozilla/sccache

Reviewed By: nicholas_rishel, Brecht

Differential Revision: https://developer.blender.org/D7466

Merge branch 'blender-v2.83-release'

Fix T75885: Mesh deform modifier not updating on own transforms

Added the missing relation.

Maniphest Tasks: T75885

Differential Revision: https://developer.blender.org/D7473

Libmv: Cleanup, spelling in comment

Libmv: De-duplicate creation of residual block

Allows to centralize logic which is needed to check which cost functor
to use for the specific intrinsics.

Libmv: Cleanup reprojection cost function

Make it smaller and more clear how and what it operates on.