Add REST API

[Sing-Li]

For some users of the leaderboard, automation for obtaining real-time statistics is important.

Add REST API to support fetching of any of the following data:

1. current sum totals of the columns, with name of columns

2. list of contributors and their ranks

3. row data for a specific contribuor, keyed by github id

4. fetch github id of a contributor at a specific rank

5. ... other interesting statistics

[Amdadullah-Raihan]

Hello, I would like to assist with this matter. Could you please assign it to me? I am eager to contribute.

[harshiltewari2004]

I would like to work on this issue. Can you please help me with it?