Add source root to python path in sphinx conf
Add source root to python path in sphinx conf

This will let the auto* extensions find our source without requiring it be
installed. This will make the readthedocs setup more sane.

pvtodorov/indra,johnbachman/indra,jmuhlich/indra,pvtodorov/indra,sorgerlab/indra,sorgerlab/belpy,pvtodorov/indra,bgyori/indra,johnbachman/belpy,jmuhlich/indra,bgyori/indra,sorgerlab/belpy,bgyori/indra,johnbachman/indra,jmuhlich/indra,sorgerlab/indra,sorgerlab/indra,pvtodorov/indra,johnbachman/belpy,johnbachman/belpy,johnbachman/indra,sorgerlab/belpy