__init__: Added __version__ var
setup.py: Updated copyright date
setup.py:

Scrape the __version__ from the package init (so the version number is
only defined in one place).
setup.py:

Added missing import.
Merge pull request #130 from larsbutler/__version__

Add __version__ to package init

[r=matley] [f=*trivial]
aligned packager.sh with the new version management
Merge branch 'master' of https://github.com/gem/oq-hazardlib into risk-from-ses
fix typo in docstring