0028954: Visualization - implement interactive object for camera manipulations

0028954: Visualization - implement interactive object for camera manipulations

Added new class AIS_ViewCube implementing interactive cube displaying orientation of the main axes of the model space in the viewer.
Each side, edge, or corner of the cube corresponds to particular orientation of the camera, and the class provides methods to move the camera to corresponding position (with animation if needed).

DRAW command vviewcube is added to use the cube in DRAW.

(cherry picked from commit cd47b946ed397b421d24a19da1928cd4d2391533)