Fixed multiprocessing issue related to OpenMP multiprocessing within pykdtree as called by pyresample. Fixed type hints.

Fixed FutureWarning for numpy>1.16: arrays to stack must be passed as a "sequence" type such as list or tuple. Updated version info.

Revised SensorMapGeometryTransformer (now fully operable) and added corresponding tests. Added boxObj.buffer_mapXY() + test. Added type hints.

Added a tolerance to get_smallest_boxImYX_that_contains_boxMapYX() to avoid float coordinate rounding issues.