Implemented final two functions in Matrix. Added Plane. Implemented Frustum's constructor. Modified Vec3.scale to match the new conventions.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@2492 822214bb-dcf7-4c8d-a767-17ae0fb20d88
Checked in the design and coding guidelines.

git-svn-id: http://worldwind31.arc.nasa.gov/svn/trunk@2493 822214bb-dcf7-4c8d-a767-17ae0fb20d88