=============
Bug fixes
---------
* In function ``astro_star``: fixed issue where the third argument of the
C function call was ``c_short`` instead of the intended ``accuracy``.
* In function ``transform_cat``: fixed issue where ``newcat_id`` was being sent
to the C function as a length-51 character array instead of a length-4
character array.
* In function ``limb_angle``: fixed issue of an extra ``=`` in call to
C function.
* In function ``cal_date``: fixed issue where ``day`` was used in two places
(input and local variable); input argument is now called ``jd``.
* In function ``state``: fixed issue in statement that checks for negative JD;
changed ``tjd`` to ``jed``.
Error handling
--------------
Added C function error handling. Error return codes from NOVAS C functions are
handled by raising an appropriate exception. However, given the way NOVAS C
does error codes it was found that some return codes from higher-level
C functions can represent more than one error. For these cases the developer
chose what was felt to be the most likely or most important error code to
escalate to an exception. All possible error codes are in the ``c_error``
dictionaries attached to each C function object, within each wrapper function,
but those with duplicate numbers are commented out at this time.
Miscellaneous
-------------
* The package should now work with Python 3.
* Improved docstring formatting.
* Changed the output formatting of ``checkout-stars-full.py`` test script to
match the output formatting of the C version
(``checkout-stars-full-usno.txt``).