Adding Ninject extension to Nimbus.

This is my first time creating a pull request, so I hope I got it right...

Anyways, this is my attempt at adding Ninject functionality to Nimbus. I pretty much just copied the patterns laid out in the Autofac and Windsor extensions. The integration test is slightly different so I could run it locally without the c:/temp/connectionstring.txt file. I added the nuspec file, but I wasn't sure if I needed to update something elsewhere to get the nuget packages to build.

I included the Ninject /package files since that seemed to be the pattern for the nuget packages in this project.

I have not used my additions extensively yet, but I will be shortly. If I find any issues, I'll be sure to fix them.

Thanks,
Zach