Fixed broken import.

Merge pull request #3 from zachartrand/v1.1.1

V1.1.1

A few functionality changes, docstring changes.

- Removed NotImplemented from __float__ and __int__ methods, as they 
were used improperly.
- Docstring changes for sphinx.
- Changed scalar property to return a Quaternion object to match the 
vector property in functionality.
- Changed unit_quaternion method to return the zero quaternion when the 
norm of self is zero (0).
- Changed docstrings of properties so they don't have "Return" in them.

Added packaging files/folder to .gitignore