Blender Git Loki

Merge functions describing overlap into single function.

Revert ovelap mode property back to enum

VSE: Transform overwrite mode

Add mode to overwrite strips on overlap instead of resolving overlap.
When overlap is created, 3 things can happen:
- On partial overlap, handles of overlapped strip are moved
- On complete overlap with smaller strip, overlapped strip is split
- On complete overlap with larger strip, overlapped strip is removed

This mode can be enabled in header.

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Demonstration:
{F10226243}

Reviewed By: mano-wii

Differential Revision: https://developer.blender.org/D11805