Reflect the new logic to calculate delta values into the API

[sudevschiz]

Initial logic to calculate recovered and deceased delta from the raw data failed as the number of cases increased and it was getting tough to assign the aggregate number to individual patients.
We revoked that calculation and made those values 0.

#61
#45

We made changes in the process and logic and the correct daily delta for recovered and deaths are now available in the StateWise sheet. This need to the updated in the delta dictionary as before.

[sudevschiz]

This has been fixed and the delta values in data.json is correct for each statewise