Implementing proportional contributions

[rustoceans]

An idea for implement the contributions of control so you can draw your github art.

I was surfing the internet and I saw this idea.

[IonicaBizau]

That's a feature I was thinking at. It's awesome that you find this! :+1:

However, the implementation in our case would be with data-presure={0-4} and with some CSS styling. A little bit difficult will be the part with the computing how many commits should be made on a day.

Waiting for a good pull request! ...sure if you're faster than me, guys! :smile:

[Unihedro]

+1 for art. Pretty colors!