Fixed typo.
Initial skeletton for lustre-specific tests.

Added a dotlustre module, which provides a (currently limited)
set of tests to verify the behavior of the .lustre/ directory
and OBF.
Renamed "dotlustre" module into "lustre"

Expanded dotlustre tests to also run more general purpose ones. Renamed
the modules accordingly.
Merge pull request #1 from hdoreau/master

Add lustre-specific filesystem tests