[ ] utils.h for common functions
[ ] drop "manipulate curvature" -> too specific [INTERFACE CHANGE]
[ ] drop C++11 and C++14 support, minimum version bumped to C++17
[ ] polyline calculation:

• current default flatness parameter is not scale-invariant
• cache parameters t for each point of calculated polyline representation
  [ ] make "applyContinuity" a static method and introduce enums for curve Start/End combinations [INTERFACE CHANGE]
  [ ] fit, join, and offset Bezier curve functionalities
  [ ] change "splitCurve" to return vector and add overload which could split curve into multiple subcurves [INTERFACE CHANGE]