Creates new substructure for arc management. Existing functions provide
wrapper to use SHAPE_LINE_CHAIN as normal, without arcs while also
permitting the addition of arcs into the chain
- Fix non optimal shape of solid polygons after inflate transform.
- Add a small extra clearance ((2 microns) when creating clearance areas
(especially, convert arc to polygons create small differences)
- Add a small threshold (1 micron) in drc test distances to avoid false positives
- fix a minor issue in TransformOvalToPolygon that created sometimes a not perfect shape
Fixes#3812https://gitlab.com/kicad/code/kicad/issues/3812
* Split up the thirdparty code into the thirdparty folder (#3637)
* Create a new kimath static library containing all the math functions
This is part of cleaning the build system for #1906.