Add cross-links to documentation

[lazappi]

Add relevant cross-links between README, vignettes, man pages etc. and the main Python Lamin documentation

[Zethson]

Is there any reasonable way for you to use sphinx? If it were possible we could make a ton of useful references to the Python docs.

[falexwolf]

I asked that question 2 weeks ago in the kick-off and the answer from Robrecht & Luke was: "we have never seen an R package documented with Sphinx".

[lazappi]

The R package structure is a lot more restricted than for Python and there is a particular format you have to use for function documentation. The current website uses {pkgdown} which takes that format and converts it to HTML.

I did find a package that converts to ReadTheDocs format instead but we would have to try it out to see if it works and makes cross-linking easier.

I guess you could make the vignettes as a separate sphinx site but then lose the function documentation and lot of automated checking.