CHANGES:

1. Add option to upload results to AWS S3 bucket
2. Remove generation of insample plots from pipeline

CHANGES:

1. `thin_samples['init_state']` --> `thin_samples['initial_state']`
2. `thin_samples['events']` --> `thin_samples['seir']`
3. add time dimension to next generation matrix
4. update downstream scripts to changes.

CHANGES

1. Most tasks touched to use netCDF4 inferencedata file.
2. Added netCDF4 metadata copy to covid.util
3. Updated model_spec.py to use xarray
4. Updated covid.ruffus_pipeline to use netCDF4 files, adding pipeline metadata
5. Updated pyproject.toml
6. Removed chunk specification in inference.py.  Defer to automatic chunking for now.

CHANGES:

1.  Added code in `summary_longformat.py` to calculate cumulative incidence;
2.  Switched from `openpyxl` to `xlsxwriter` for lower memory usage when writing
    to summary_longformat.xlsx.

CHANGES:

1. Introduced default unit traffic flow;
2. Removed old test data from data directory.  This now contains real static data only.
3. Brought README.md up to date.
4. Removed extraneous files from root project directory.

All project config now goes in `pyproject.toml`.