CLI stall when no logfile is provided
Set __version__ in the lib

Attempt to respect PEP 8 and 386 to provide version tracking inside the library.

* https://www.python.org/dev/peps/pep-0008/#version-bookkeeping
* https://www.python.org/dev/peps/pep-0386/
Merge pull request #10 from romain-dartigues/rework-1

Set __version__ in the lib