- including xBoundingBox.h and/or adding using namespace xgeom and/or
  changing xtensor::xBoundingBox.h to xgeom::xBoundingBox, and/or reordering
  headerfile inclusion by library origin, and if any of the previous,
  clang-format.
- Modifying CMakeLists.txt when needed to remove xGeom and add
  xGeomTools and/or xDistanceNearest and/or xScanElement
- removing useless Mechanics_c destructor in some xxxx-test/xxxx/main.cc/h