Bug fix: MultiSearch was returning derived types as base type (as specified in generic)

Applied patch https://github.com/Mpdreamz/NEST/commit/c48f9477e0698d9d46499793c43be96c46ec0e11.patch via https://github.com/Mpdreamz/NEST/pull/352
implementing Index Status API for issue #299

Added ElasticClient-Status with methods to retrieve status
Added StatusParams to allow query string property setting
Added StatusResponse and child Stat objects to deserialize response
Added Status API tests to Nest.Tests.Integration project
Adding documentation for Status API
Adding support for shard_size to TermFacetDescriptor issue #423
Merge pull request #1 from richclement/feature-branch

Adding support for shard_size to TermFacetDescriptor issue #423
Merge pull request #425 from richclement/master

implementing Index Status API for issue #299
Merge remote-tracking branch 'upstream/master'

Conflicts:
	src/Nest/Resolvers/Converters/MultiSearchConverter.cs
Relaxed type constraint on Document method for UpdateDescriptor so that any partial document may be supplied for upsert
Added a comment for the Upsert method to clarify its usage
Updated BulkUpdateDescriptor with same changes as UpdateDescriptor
Changed Document type from object to K parameter
Changed Upsert() in Bulk/UpdateDescriptor parameter to take an object of type T and not K, as Upsert() represents the (full) document to insert if an existing document does not exist
CustomAnalyzer ctor to set AnalyzerBase.Type

By providing a ctor that sets the Type property users will not need to remember
to set the type property manually.

Removing the default ctor would be a breaking change.  Marking it obsolete
should lead most people to "the pit of success".
Merge pull request #430 from 121cast/any-partial-doc

Allow any object type to be used for a partial update during upsert
fix #434 added support for execution_hint on the terms facet
support dictionary key evaluation
Merge pull request #440 from azubanov/master

support dictionary key evaluation
Remove obsolete attribute
Merge pull request #431 from sschlesier/CustomAnalyzer-ctor

CustomAnalyzer ctor to set AnalyzerBase.Type
Renamed QueryString to Query on the MatchQueryDescriptor