Reorganize Code

[mccalltd]

Need/want to reorganize:

• Web API bits can be centralized in AR.Web.Http
• Non-Web API bits will go in AR.Web.Mvc
• RouteAreaAttribute will go in AR.Web.Mvc
• Improve parsing. Pass some responsibility to the RouteSpecification when logical.
• Constraints need to use actual types in ctor. Need to then convert string value during instantiation.
• Flatten the heirarchy of classes somewhat.
• Update configuration syntax, and auto-scan all loaded assemblies.
• Kill obsolete code