Nightly Builds

For each project, I'd like to have a nightly build that will

1. `cabal install` successfully
2. `cabal haddock`
3. `git clone $WEBSITE`
4. replace (awk/sed?) the requisite paths in the docs
5. copy the docs into $WEBSITE/static/doc/$PROJ
6. `cabal sdist`
7. copy the 'sdist' artefact into $WEBSITE/static/artefacts/
8. `git add` the changes to $WEBSITE
9. `git push origin master` to deploy the website changes