Fix bug where new mappings with index_options break mappings

This is a bit of a band-aid.  We should add index_options as an actual keyword argument and instance attribute (and anywhere else appropriate).  However given that the mapping attributes can change, we should keep **kwargs to prevent future breakage
Merge pull request #346 from merrellb/patch-1

Fix bug where mappings with index_options break mappings
Merge branch 'master' of https://github.com/aparo/pyes into feature/cleanup_deprecation