[#53196411] JSONP can NOT be used for XSXHR if response is not JSON.

Read up on JSONP : http://en.wikipedia.org/wiki/JSONP
CORS: http://en.wikipedia.org/wiki/Cross-origin_resource_sharing
Is the "modern alternative" however PT does not provide the
 Access-Control-Allow-Origin: * header.  There is a request out to PT to
allow this header so that exactly what I was trying to do is possible.

http://community.pivotaltracker.com/pivotal/topics/cors_support_for_api

Since its not going to happen anytime soon I used good ol PHP to set up
a proxy to make the requests to pivotal for the JS.

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