- Make Datums colorable and transparent
- Change default datums color to yellow and transparency to 60%
- Rework Lines and Points datum view provider
- Add ViewProviderDatum::defaultBoundBox()
PartDesign: make datum features work outside of body/part
PartDesign old workflow: remove a few messageboxes about no part
PartDesign: old workflow: multitransform without body
Still has visibility issues, but generally works.