- Added license information for the project so it's displayed with pip show pysunspec2.
- Updated the unimplemented point verifications for float32 and float64 points.
- Used a cache for model definitions to reduce disk I/O when the same model definition is loaded multiple times.
- Initialize FileClientModel's parent class FileClientGroup with the proper point class of FileClientPoint
- Migrate setup.py from distutils to setuptools