Update git page

[prasanna1211]

1. Update Readme. Readme should contain how to install, how to use, links for documentation, customization, theming, design guidelines

2. Add how to contribute section

3. Add license

4. Add Top X number of contributors section (Automate it).

[rishichawda]

These two can be used for contributors -

https://github.com/DavidWells/markdown-magic-github-contributors - since already using markdown-magic for build bages ( Reference PR: #149 ).

or

https://github.com/jonschlinkert/github-contributors - This also has same kind of implementation. Basically, the markdown-magic's contrib plugin uses this package's implementation.

[rishichawda]

@prasanna1211 @KRRISH96 2 and 3 are completed. I guess we can consider 1 as done for now?

[KRRISH96]

We can use this

https://github.com/DavidWells/markdown-magic-github-contributors - since already using markdown-magic for build bages

[rishichawda]

I've opened a separate issue on #247 for the remaining task. Closing this now.