Check and fix README links
Clarification and motivation
README files of our Haskell packages contain relative links which are not handled well by Hackage. If you open morley or lorentz on Hackage you will find some broken links there. Indigo on Hackage seems to have broken links as well, but they seem to be fixed in master.
Acceptance criteria
All .md files uploaded to Hackage (in all packages, not just those already on Hackage, keep in mind that other packages can be uploaded as well) are checked and do not contain links that Hackage doesn't handle properly (e. g. relative links).
Edited by Ivan Gromakovskii