Link readthedocs from repo README.md

[jlapeyre]

This would make the docs more discoverable.

[gabbyprecious]

Can you try explaining what you want achieved better, I would like to contribute on this.

[jlapeyre]

Thanks for offering. I mean that the documents https://forest-benchmarking.readthedocs.io/en/latest/
could be linked to from within https://github.com/rigetti/forest-benchmarking/blob/master/README.md

Here is an example of how its done in the pyquil repository https://github.com/rigetti/pyquil/blame/master/README.md#L24

In fact there is a line of "badges" at the top of the README.mds. In many other repos, a badge is included that links to the documentation. Neither pyquil nor forest-benchmarking have this badge in their READMEs. But, it would be a good idea. For instance, this repo https://github.com/FluxML/Flux.jl has a badge (labeled "docs|stable") that links to its documentation.

Here is a link to the line that codes the badges in Flux.jl: https://github.com/FluxML/Flux.jl/blame/master/README.md#L5