Fixed wrong integration tests config.
Add Batch property to PUT / POST request objects.

When specifying the Batch property, batch=ok is passed as a parameter
to the CouchDB / Cloudant API.

Given that this is rarely used, it's not exposed in the document PUT /
POST helper methods - you have to construct the request objects fully in
order to use it.
Do not join unless there is something to join.
Since Accepted writes and other stale changes might not show up in the
view, we query it twice when deleting docs after integration tests.
Clean.
Accepted tests expectation tweaks.
MyCouchJsonWriter is now DocumentWriter.
Arg naming.
Fiddling with a DocumentAttribute for Meta-data.
DocumentMeta for manual control of serialization of docs.
Renamed tests.
-Injectable DocumentMetaSerializationProvider
-Moved SerializationConventions to SerializationConfiguration
Use await instead.
Using portable class lib for the JSON files for test data to get
simpler handling and get xUnit to work.
Updated info about tests etc.
DefaultSerializer vs DocumentSerializer vs EntitySerializer
Proper attribute usage.
Tweaks to get better err.
Updated Nugets.
Corrected test after FluentAssertions update.