Push construction of routing maps into Sites

Summary:
This enables CORGI.

Currently, AphrontSite subclasses can't really have their own routes. They can do this sort of hacky rewriting of paths, but that's a mess and not desirable in the long run.

Instead, let subclasses build their own routing maps. This will let CORP and ORG have their own routing maps.

I was able to get rid of the PhameBlogResourcesSite since it can really just share the standard resources site.

Test Plan:

• With no base URI set, and a base URI set, loaded main page and resources (from main site).
• With file domain set, loaded resources from main site and file site.
• Loaded a skinned blog from a domain.
• Loaded a skinned blog from the main site.
• Viewed "Request" tab of DarkConsole to see site/controller info.

Reviewers: chad

Reviewed By: chad

Differential Revision: https://secure.phabricator.com/D14008