Improvements:
- Increased CHUNK size as per miniz instructions
- Added tests for very large arrays in NPZ files
- Added some CI tests to catch issues across platforms
- Removed the internal IO streams in favor of just using stringstream
- NPZs can now be read from and written to memory
Bugfixes:
- Fixed an issue where very large arrays in NPZ files would throw an error
- Fixed a bug with mac builds due to deprecated APIs