Introduce the ability to store cells which share metadata in the same HDF5 file, and more fields to the metadata.
What's Changed
* Add ability to store multiple cells per HDF5 by WardLT in https://github.com/ROVI-org/battery-data-toolkit/pull/63
* Warn if version of metadata is different, ignore failures by WardLT in https://github.com/ROVI-org/battery-data-toolkit/pull/66
* Introduce fields in schema to describe synthetic data by WardLT in https://github.com/ROVI-org/battery-data-toolkit/pull/64
**Full Changelog**: https://github.com/ROVI-org/battery-data-toolkit/compare/v0.3.0...v0.3.1