Programmatically upload bokeh js/css to the container

This PR add a simple and isolated script to upload bokeh.[min].js[css] files to Rackspace.
This helps in the release process and BEP-2 has to be modified accordingly after merging.

I think we should go ahead and add some kind of error/problem checking and logging too. Maybe better to have this be a python script that uses `pycurl` or `subprocess`?