Doc fixes

[HHHartmann]

Fixes #no issue.

• This PR is for the dev branch rather than for the release branch.
• This PR is compliant with the other contributing guidelines as well (if not, please describe why).
• I have thoroughly tested my contribution.
• The code changes are reflected in the documentation at docs/*.

<Description of and rationale behind this PR>
Fix doxumentation:

• include windows luac.cross attached to releases in the tools matrix
• fix minimal LFS example
• fix example in docs/index.md
• change master -> release

[marcelstoer]

That's possibly fixing a non-existent bug, see https://nodemcu.readthedocs.io/en/latest/getting-started/#task-os-selector

-> #task-os-selector

In case GitHub and RTD use different to-anchor algorithms (caused by the '/' ?) then maybe we need to adjust the title.

[HHHartmann]

Oops, should have checked at RTD. changed the title.

[HHHartmann]

Btw: is there a way to check RTD before at least having it on dev branch?
Btw2: Have you seen the PR number?

[marcelstoer]

Btw: is there a way to check RTD before at least having it on dev branch?

Two options:

• Create a RTD account for yourself and create a project pointing at your forked NodeMCU repo.
• Install MkDocs locally and run mkdocs serve in the NodeMCU root (ignoring the warnings about invalid source code references). Question is: which MkDocs version? I lost track.

Btw2: Have you seen the PR number?

😄 not until you mentioned it, congrats for pulling a repdigit ticket number

[nwf]

There are a number of /master/ URLs in README.md that could stand to be modernized while you're here.

[vsky279]

@HHHartmann Gregor, I suggested few other corrections sending a PR directly to your branch.

[nwf]

LGTM