CHANGE:

1. Reverse experimental selection of last but one xi.
2. Updated template for most recent flow data

Note: in the actual analysis, the effect of December Tiers was
removed.

CHANGES:

1. New data adapter `read_challen_tier_restriction`
2. Modified `model_spec.py` to use new data adapter

CHANGES:

1. Re-introduced Tier lockdown covariates.  National lockdown covariate is set to 0 because
   we cannot identify this from the time-varying baseline force of infection.

2. Added inference on variance parameter for the temporal Gaussian process on beta.

CHANGES:

1. update date and data name in enqueue_pipeline.sh
2. update infection time initialisation in model_spec.py

CHANGES:

1. Implemented log-linear model for weekday effect in I->R hazard;
2. Updated summary.py and within_between.py to match;
3. Implemented linear random walk for new gamma0 parameter.
4. Implemented per-parameter data structure in output HDF5 file.

CHANGES:

1. Re-implemented trace_fn
2. Implemented new Posterior class in `gemlib`

CHANGES:

1. Updated the model to use the new gemlib library;
2. Removed automatic deletion of results directory by prepare_config.py;
3. Parameterised `gamma` prior parameters and added to template_config.yaml;
4. Updated within_between.py to use global configuration file.

MCMC update kernels in `interface.py` changed to reflect new
AdaptiveRandomWalkMetropolis interface.

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