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.

@damian that URL is what I am saying is too short :)

With http://cdn.pydata.org/release/bokeh.0.X.0.js now everything is at the very top. But there are other pydata projects that might want to use the CDN we should be better neighbors and put all of our stuff in a "subdir" so that the URL is this:

http://cdn.pydata.org/bokeh/release/bokeh.0.X.0.js