Merge pull request #255 from patrick91/distance_filter

Distance filter
Add Patrick Arminio to CONTRIBUTORS
Fix index creation problems

When defining a mapping, the fields need to be in a 'properties' dict.
Elasticsearch < 1.2 didn't complain about these, but Elasticseach 1.2
does.
Tweaking the version for 0.10.1 development

We're going to push out a 0.10.1 before moving on to 0.11.
Fix travis failures

* Add more Elasticsearch versions to the Travis matrix.
* ElasticUtils may not work with Django 1.7. At a minimum, we know that
  tests don't pass. For now, restricting the Django version to <1.7.
Added search_raw.
Merge branch 'raw_search'