Changes for patch:

1. Solved issue for new metrics for being added to originally PosRateNew.ipynb (currenly unified_states_metrics.ipynb)
2. Added metrics calculation (both original and new) for district level (named unified_dist_metrics.ipynb)
3. Solved issue for output csv to append repeating data, resulting in 7 times the rows than original
4. Changes in code for outputting shifted data for 9 days for all Rt metrics

Tip for reviewing process:

1. Changes are marked with comment "#New".
2. Functions are replaced and old one are kept in same cell with multiline comment