Nth PR on develop branch for easybuild-docs, for N=5

still bits and pieces to improve, but ok to receive the first round of feedback
some notes:

- `--help`/`-H` spit out the long help info (i.e. including long option names), `-h` only includes short option names
- mention that this is the best way to query for certain information, since this is in sync with the actual EasyBuild version being used