WIP: Improve support for embedded resources and NuGet it up

This PR seeks to put embedded content on the SDHP by fixing a remaining issue and working out the wiring for a Nancy.Embedded NuGet.

## Questions i have

When wiring up embedded views for Nancy, i followed [this post](http://simoncropp.com/embeddingviewsasresourcesinnancyfx) by Simon Cropp. It was pretty simple, but according to #510 it sounds like there was 

## todo
* [x] Fix issue with embedded views in an outside assembly mentioned in [this mailing list post](http://groups.google.com/d/msg/nancy-web-framework/9N4f6-Y4dNA/ZcGu35SBMoYJ). Thanks for the fix, Rex!
* [ ] Add an extension that allows an `AddDirectory` for embedded static content, similar to the extension method on the default `StaticContentConventions`
* [ ] Help me decide what SDHP means for wiring up embedded views and include it in Nancy.Embedded project
* [ ] Make sure issues discussed in #510 are taken care of here