Fix typo
Migrate project to Calendar (unless Ocamlnet)
Merge pull request #6 from Chris00/master

Present better the documentation of Syndic.Rss1
Update README
Update travis
Merge pull request #7 from Cumulus/migrate-to-calendar

Migrate project to Calendar (unless Ocamlnet)
Complete signature of RSS 2.0 error
Improve the documentation of Syndic.Rss2
Improve the documentation of Syndic.Atom

In particular, the constraints enforced by the type system have not
been restated in the documentation.