vlight command has been revised to provide more friendly syntax.
Command now accepts light index or name as first argument.
Added arguments -enable/-disable for managing enabled state.
Added argument -reset to reset light parameters to default values.
V3d_Viewer::SetDefaultLights() now sets names "headlight" and "ambient" to created lights.
Graphic3d_TypeOfLightSource enumeration values have been renamed to avoid shortcuts.
Draw::Atof(), applied corrections to avoid explicit new/delete calls.
A new command vbackground is created. Old background commands are made aliases for the newly created command (including vsetdefaultbg).
Tests are modified using newly added command vbackground.
-Meaningful texts are provided instead of commands in File menu (e.g. restore->Load Shape (restore))
-tk_getOpenFile is used in "open file" dialogs
-tk_chooseDirectory is used in "change directory" dialog
-Added menu "Help" with submenus "System info", "Commands", "About", "User Guide"
-Added menu "Samples" with submenu "View samples"
-Added menu "Load" with submenus "pload <Module>"
New sample created for ray tracing in DRAW: samples/tcl/raytrace.tcl, rendering OCCT bottle with glass on a rectangular table, with shadows and reflections (if OpenCL is available). Sample bottle.tcl retains only modeling part.
