Point geodjango submodule away from missing commit

Commit d3c15c108b48dcd1ac9fec48d4257d46714adbe2 is missing from
niran/chef-geodjango (!!).  Fix this by pointing to the last good
commit.
Merge pull request #2 from rtucker/86c43e1c415046161273565554ea5fd079e8f9df

Point geodjango submodule away from missing commit