* 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.
Changes SHAPE_CONVEX to SHAPE_SIMPLE to better reflect the limitations.
Changes SHAPE_LINE_CHAIN::PointInside calculation to allow points
strictly inside a line chain
Fixes: lp:1768862
* https://bugs.launchpad.net/kicad/+bug/1768862
- CACHED_CONTAINER::GetVertices: removed useless and unused function
which does nothing but tainted the API
- SHAPE_LINE_CHAIN::Collide( const BOX2I& aBox, int aClearance ):
removed an outdated function with assert(false)
- SHAPE::BBox(): fix a small typo in the doc string