Various architecture upgrades to support this.
Creating a BOARD now requires a valid PROJECT, which caused
some (mostly transparent) changes to the Python API internals.
ADDED: Project local settings file
CHANGED: Board design settings are no longer stored in PCB file
CHANGED: Net classes are no longer stored in PCB file
CHANGED: Importing board settings now reads boards, not just projects
Fixes https://gitlab.com/kicad/code/kicad/-/issues/2578
Fixes https://gitlab.com/kicad/code/kicad/-/issues/4070
Replace SEVERITY_ERROR by RPT_SEVERITY_ERROR to avoid collision with a system definition.
Replace other SEVERITY_XXX by RPT_SEVERITY_XX for consistency.
Fix compil warnings and some other compil issues.
Introduce the concept of a DRC_PROVIDER which allows
to separate the various DRC functions to their own
areas. This allows, amongst other things, a slimmer core
DRC class, and allows DRC functions to be separately testable.
The courtyard DRCs (overlap, missing and malformed)
are the first victims, so instrumentation can be added to this function.
Add some unit tests on this DRC function, as well a few re-usable PCB-based
utility functions in a library (qa_pcbnew_utils) that could be shared between
unit tests and other utilities.