README doesn't link to documentation.

README.rst states "The best way to get started is to read the documentation on GitHub." but just links back to itself. https://github.com/ARMmbed/mbed-cli/blob/master/README.rst

Include link to documentation.

Open README.rst and inspect the sentence that says the documentation is on GitHub, along with its current self-link. Replace that link with the project's documentation destination, then verify the rendered README points to the documentation rather than README.rst.

Written by the indexing model from the issue text.