remove name_by_class and move class_by_name into neo.core
move classes_inheriting_quantities to classes
move classes_necessary_attributes and classes_recommended_attributes into the classes
remove now-empty description.py
Merge pull request #134 from toddrjen/no_description

Remove description.py entirely
Add StimfitIO, including unit tests, to neo.io
Use stimfit format hdf5 files for unit testing
Only raise ImportError when StimfitIO is actually used
Improve StimfitIO docstrings
Use single argument (stfio.Recording or filename) for StimfitIO
Comply with pep8 and use more Pythonic expressions in stimfitio.py
Correct t_start in StimfitIO