More sweeping changes

These late nights are slowly killing me, but it's worth it - development has been progressing at its fastest rate in months:

• The scripting engine has been revised for a fourth time, and now operates on C# scripts without the use of yield-powered coroutines.  This is, according to conservative estimates, about a zillion times better.
• Runtime serialization is now powered by Google's Protocol Buffers (protobuf-net) as this works on all platforms and is ridiculously fast compared to XML.
• Support for spoken dialogue has been added.

Also, many thanks to David Gouveia who very kindly sent me the source to his excellent A* & Clipper powered pathfinding system.  I'm hoping to be able to leverage this into XAGE as a direct replacement for the old, clunky Walkbox system, providing I can crowbar in some additional functionality:

• Separate walkable polygons (that can be enabled/disabled at runtime).
• Closest-point identification (when clicking outside of a walkable polygon).

As I'm happier with the current state of the engine than I have been for a long time, I've recently been collaborating on a little something with a gentleman who has been proven to be an impressive 30.4 times better than Ben10.  More on this over the next month or two.