angelscript: Branch started by importing AngelScript SDK.
angelscript: AngelScript comfortably integrates Vec3d.
angelscript: Add bytecode save function
angelscript: Adding addition operator for AngelScript, without sweat.
angelscript: Adding arithmetic operators to Vec3d
angelscript: Add dstring type definition.

There are only constructors and destructors.  We will add string
manipulations.  I wonder how to deal with C-string with AngelScript.
angelscript: Implemented string with gltestp::dstring for better integration.
angelscript: Added all operations for Vec3d.
angelscript: Add Quatd class with all its method definitions.
angelscript: Testing integration to the game engine.

It seems to work well with x64 too, but we had to fix a code in the
library.

Just like Squirrel script, an adaptation source is provided, whose name
is asadapt.cpp.

The testing code is based on angelscript/samples/tutorial.