Added "in" as an abbreviation for "inches"
Added "lightyear" as synonym for "light-year"
Added MPH
Added kph
Add support for more ufuncs and improved testings.
Added support for more NumPy funcs

- All NumPy test pass in Python 2.7.
- Bitwise related test removed.
Moved tests inside package
Improved naming of methods and added docs
Implemente UnitRegistry().validate to crawl the entire registry.