few more docs

Hi,

although I might touch these sources again tomorrow, I thought it's good to open a PR in order to receive early feedback (mostly of crude type about missing pieces/paragraphs). Yet, any feedback is welcome :)

tia, F.
simply use `$` as a prompt, without anything before it

also: what's reasonable w.r.t. version? Just drop this imho, people who don't know what this is will be confused ("is this command needed to make the installation work?"). You should also be using `module --version` instead btw.