Small corrections

Other small fixes
Merge pull request #472 from gimmy/patch-3

Small corrections
add last CFP to news
Merge pull request #474 from garrigue/master

add last CFP to news
Update OCaml meetings page with the next OUPS event
Merge pull request #476 from braibant/patch-1

Update OCaml meetings page with the next OUPS event
Oasis tutorial.
Make individual commands real code blocks.
Add OASIS tutorial