Added ability to pass in specific date_time attributes to the has_time_z...

...one method with tests. Updated readme and bumped teh minor version. Moved private class methods module into it's own file.

changing the tests little

silence deprecation warnings commented out

All tests passing, but the code is a little ugly and a little too complex. Also there's no check to see if any of the indicated fields exist, which is becoming more important.

cleaned up initialization method. Moved private class methods into it's own file.

Added test to check that the time zone attribute is being set correctly for base classes.

update versioning info

moved require location

Updated the readme to account for the added feature.

Fixing gempspec file. Adding and remove newlines.