Add hotspot districts

[MGMD-96]

The following districts may be a good start, and we can expand to more districts later:
MH- Mumbai, Thane, Pune, Palghar, Aurangabad
TN- Chennai, Chengalpattu, Madurai
TG- Hyderabad
KA- Bengaluru Urban
GJ- Ahmedabad, Surat
HR- Gurugram
WB- Kolkata

Source api: https://api.covid19india.org/v3/data-all.json

Have to input populations of these districts to calculate population-adjusted indicators. I have compiled the same and put in the repo as Population_districts.csv

Will run the existing estimation scripts for these districts. Where data is available, indicators will be calculated.

Output district json and csv to be sub-structured into current state level json and csv. [OR] Output json and csv for districts to be separate from state json and csv.

Limitations

• Testing data is not avail for most districts in source API. Can look for district bulletins independently to add that data.
• Google mobility is not avail for district level.