Ability to push a record to several indexes.
Merge branch 'master' into multiple_indexes

Conflicts:
	lib/algoliasearch-rails.rb
	spec/integration_spec.rb
Add missing highlightPreTag/highlightPostTag settings
Bump to 1.9.5
Fixed per_environment option not working on additional indexes
Ability to define slaves from algoliasearch block
Merge branch 'multiple_indexes'