Write a better README with many examples

[metal3d]

Users should not need to go to the documentation (readthedoc) page to understand and have examples - so, we need a better README file.

[metal3d]

I actually made it in doc directory, but images are broken (I abandoned my blog for a time), I need to recreate images.

[mintxdp]

Hey! I want to make a good readme. I forked the repository and cloned it but i am not able to create a branch to create changes.
It,s saying ,you are not allowed.