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- Do not disable track when tracking frame-by-frame and tracking
threshold became bad.
- Show anchored image in track preview widget.
- Do not show search area for non-selected and disabled markers.
- Keep anchor constant position when sliding offset parameters in panel.
- Re-enabled occasionally disabled openmp for tracking.
- Renamed clearing operator so now buttons are more clear.
- Updated eigen to the very recent version.
NOTE: I had to enable static aligning again due to it gave crashes
when tracking on my new laptop. I'm not sure it'll work fine
on another systems.