Added support for passing in HttpServer to UseNinjectWebApi

This is needed to be able to use Batch Endpoints in WebAPI 2.

Ref:
https://aspnetwebstack.codeplex.com/workitem/1025

https://aspnetwebstack.codeplex.com/SourceControl/changeset/7d218ace76562c28b6858f50e040888e9e1c5099
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