Initial draft for DefineSection \ RenderSection. This change is based on
changes to the Razor parser to enable Razor to generate HelperResults for
section instead of void delegates.
1. Areas defined by the Area attribute
2. Areas are a routeconstraint on the actiondescriptor
3. Areas find pages through route values
Other changes:
1. Remove Path from ActionDescriptor - It doesn't make sense with this change
2. Add sample Area
Pranav K
Ryan Nowak
Yishai Galatzer
David Fowler