row-category updating, moved python module to separate repo, removed JS dependencies

Row-category updating has been improved and now categories can be returned to their original state. Jquery-UI is no longer a requirement. The requirements have been cleaned up (in the process of building an IPython widget).

The clustergrammer python module has been moved out of this repo and put into a separate repo: https://github.com/MaayanLab/clustergrammer-py. This module can now be installed using pip.