- separate validation, geometry and reference handling into
individual files
- improve 3d reference geometry handling
- eliminate duplicate dim creation code
- add Dimension reference repair dialog
- Refactor formatting out of DrawViewDimension
- move dimension repaint control to ViewProvider
* reimplement ViewProviderDimension::setupContextMenu() to show menu item to start editing it
* fix TaskDimension::accept() and TaskDimension::reject()
also fix issue that tolerance could be set despite theoretically exact is true under some circumstances
also some wording improvements
also a minor fix to use 0.0 instead of DBL_MIN