Remove the inheritance from `TrackPerson` in favor of composition, this allows a better handling of interactions with the `TrackPerson` as changes now go through defined interfaces.

Main changes:

* `TrackPerson` no longer **is** a `QList<TrackPoints>`
* `TrackPerson` now **has** a `QList<TrackPoints`
* new function `deleteFrameRange` which will delete a range of frames, but leaving no gaps in the middle
* `lastFrame` is now compute and not stored, hence no need to update it
* `firstFrame` is set when creating a `TrackPerson` and will be updated when needed automatically

Resolve "Transform  c3d file"

Closes #393

See merge request !283

Resolve "Ease usage of c3d visualization for time synchronization"

Closes #391

See merge request !279

fix: loop with different frameIn/frameOut

Closes #392

See merge request !280

Resolve "More clear error message: "Duplicate entry for markerID=...""

Closes #352

See merge request !276

changed File-Extension Check to be Qt::CaseInsensitive

Closes #317

See merge request !277

fix: wrong center after opening another project

Closes #387

See merge request !274

The image center (or principal point) could be set wrongly if the previous project had a significantly lower resolution, disallowing values for cx,cy such as the correct ones for the next project.

-> load video (and therefore imagesize) first

Resolve "Add tab where the logging output is displayed"

See merge request !233

Resolve "Make autosave parameters accessible via GUI"

Closes #336

See merge request !271

Context menu no longer moves the track point

Closes #386

See merge request !273

Stop tracking before reaching the used border

Closes #77

See merge request !269

Catch error in openProject, show message and reload old proj

Closes #369

See merge request !260

New procedure for dealing with invalid pet-file:
- save current state before loading new file
- open new file
- throw exception on erroneous value
- catch exception at top level and restore old state
- show error message

Resolve "Use `USER`-directive in Dockerfile"

Closes #354

See merge request !272

Resolve "Delete dead code in CoordItem"

Closes #380

See merge request !270

- Delete some dead code in CoordItem
- Slightly refactor `paint`-method

Gray out calib (3/N)

See merge request !267

- Introduces `ExtrinsicParameters`-Struct
- Extract `ExtrinsicBox` from `Control`

Unload loaded video when loading pet with empty SRC

Closes #375

See merge request !268

Extract Widgets for "Grey out calibration tab" (2/N)

See merge request !258

- Move slots to FilterBeforeBox when concerning its elemets
- Fix Tab order of new extracted widgets
- Delete dependency to Control by AutoCalib

Resolve "Refactoring of findCodeMarker-method"

Closes #368

See merge request !254

Use repaint-call in updateImage to mitigate flickering

Closes #247

See merge request !265

Fix formatting

See merge request !266

Remove TIME_MEASUREMENT macro

Closes #120

See merge request !264