Bump the version in _oasis

Also add an author — because it was added by hand to the OPAM package
https://github.com/ocaml/opam-repository/pull/2456/files
Add constructors for Atom.
Remove the unit argument in mk_source and reorder arguments.
Remove the `mk_` prefix.
Fix travis script
Fix version of uri
Downgrade uri
Update README
Merge pull request #47 from Cumulus/fix-travis

Fix travis script
Merge pull request #46 from Drup/constructors

Add constructors for Atom.
Moves Syndic_rss2.Date to Syndic_date internal module because it may be used by other modules.
Commit Syndic.Opml1
Use ocp-indent and expansionState may now be empty.
Merge pull request #48 from Eyyub/master

OPML 1.0 support
Remove trailing whitespace