docs for package recipe as a webpage

[raisjn]

another way of presenting the information in https://github.com/toltec-dev/toltec/blob/testing/docs/package.md would be as an interactive webpage, where it shows an example package file and when you hover over a section, it presents the relevant information from package.md

combining this webpage with the text from contributing.md (which talks about how to compile, install and test a package) would then drive further contributions