ConvexPolytope: added implementation.
Prism: optimized computeOutwardNormalVector().
PhysicalEnvironment: added polytope.
Rotation: added a polytope example.
ObstacleIntersectionTest: added a polytope test.
ConvexPolytopeTest: cosmetics.
Prism, Cuboid: added computeVisibleFaces().
Prism: get polygon points as const std::vector<Coord>&.
Prism: improved error-checking.
ObstacleTest: dropped some unrelated examples out.
ObjectCacheTest: updated example.
ObstacleIntersectionTest: updated xml.
ConvexPolytopeTest: added convex combination test.
PhysicalEnvironment: extended with viewAngle support.
PhysicalEnviroment: fixed z coordinate of center.
ObstacleIntersectionTest: updated examples.