Support for value of None in MoneyField.compress.
Leaving a MoneyField blank in the Django admin site caused an issue when
attempting to save an exception was raised since Money was getting an
argument list of None.
Merge pull request #88 from rvause/master

Support for value of None in MoneyField.compress.
Version bump
add support for django 1.7 with migrations
Merge pull request #93 from w00kie/django1.7

add support for django 1.7 with migrations