fix(package): typeerror with blank reqs
fix(package): typeerror with blank reqs

The following will always throw an error:

    >>> self._requirements, self._requirements_file = None
    Traceback (most recent call last):
      File "<package.py>", line 91, in <module>
        self._requirements, self._requirements_file = None
    TypeError: 'NoneType' object is not iterable

dsouzajude/lambda-uploader,rackerlabs/lambda-uploader