Downgrade elasticsearch-py module to 0.4.x.

Need to be compatible with ES 0.90, because that's what's on staging and
production ES servers, so need to use elasticsearch-py 0.4.x branch.
Merge branch 'master' of github.com:aptivate/360giving-demos

Conflicts:
	360giving/deploy/pip_packages.txt
Switch back to using our own branch of Haystack.