Changed master to be 0.5.2.dev0
Implements __int__ and __long__ for Quantity

Close #170
Implements tests and code for real, imag and T properties

Close #171
Require setuptools to install

Close #169
Added context manager to close resource after reading.
Changed deprected assertEquals to assertEqual
Updated CHANGES
Added tests and fix for multiparemeter contexts

See #174
Removed unused regex
Updated CHANGES
Preparing release 0.5.2
Back to development: 0.5.3
Merged 0.5.2 into develop
Added CHANGES_DEV file to compile changes in develop branch