Add System.Web assembly reference to impacted packages

[mwpowellhtx]

Such as, when I subscribe to the Autofac DI package, System.Web.Hosting cannot be found. That would not be an issue if System.Web were included in the package References, not Dependencies, but References.

[mwpowellhtx]

Somewhat tangential to this question, am I correct in observing that the MvcModule and MvcSiteMapProviderModule classes are "auto-generated", that is, included with the package. I'm not sure I must have missed that detail in another iteration on another project. Thanks!