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.
I thought about PutIndexRequest but later on removed the prefix thinking that I might be able to reuse it for delete as well (for that too, it takes .similar params in request and returns just a success/failure msg).