Must:
- implement a basic glob function to replace the Str implementation (*, ?). 
- add more test to the test.ml file ( should have at least 200 test - only 133
  at the time I am writing this line )
- create a URI parser, in order to be able to adress different filesystem using
  the same string (example file:/coucou/ to indicate the subdir coucou of the
  current dir)
- install
- pathchk


Wishlist:
- Create a libtar-ocaml, to handle the tar format
- Investigate on the different UNIX command that should be great to have...
  Maybe go and see if some interesting command exist on other OS...