Pyspssio

**Full Changelog**: https://github.com/stspec/pyspssio/compare/v0.1.0...v0.1.1

First release with main functionality working.

- Open/close files
- Switch I/O mode and encoding based on file properties
- Read/write header attributes (metadata)
- Read/write/append data
- Datetime conversion

Tested on Windows 10 x64 and Ubuntu 20.04 x64. May work on other Linux distributions and MacOS, but not tested.

Initial alpha release