Cloudant query support

Added code to create a simple index with integration tests using Cloudant query API #53. Before adding more features, wanted to have a quick review of the components. We don't have querying yet. If okay, will add delete/listing of indices, followed by query.
Shall this only take one serializer? Should it not also take the "Document configured serialzer" for use in e.g. `FindResponseFactory`? Look at `Searches` and the `SearchIndexResponseFactory`.

You don't need to change. Just let me know.