Oasis tutorial

I'm working on an oasis tutorial for quick setting up of a project. The target of the tutorial is newcomers to ocaml who just want to get stuff to work. The motivation for this was "I'm repeating the same thing on #ocaml every time a beginner want help to set up a project, so I should write it down." :)

I would like to collect early opinions both on grammar/spelling and on the content. I'm also looking for other interesting oasis use cases for the example section.

Few questions :
- Should I use a more meaningful example than "foo" and "bar" for the imaginary library I'm describing ? In this case, does anyone have an idea ?
- Should I add a "Tips" sections, for very small but sometime useful informations (@jpdeplaix mentioned "how to remove the symlinks", for example) ? We could also mention some common pitfalls here (I'm waiting for propositions). 

I will rebase everything before merge, in order to make the log clean.

cc @gildor478