Add new class Font_BRepTextBuilder for generation of formatted BRep text.
Delete method Font_BRepFont::RenderText(), which should be replaced by Font_BRepTextBuilder::Perform().
Add one more pre-defined Z-layer Graphic3d_ZLayerId_BotOSD.
Define new Transformation Persistence flags Graphic3d_TMF_2d and Graphic3d_TMF_2d_IsTopDown
for displaying objects in screen coordinates.
Anchor point defines angle of the screen to display the object in similar way as for Graphic3d_TMF_TriedronPers.
Extend Draw Harness command vdisplay with new options:
-overlay as alias for -toposd.
-underlay and -botosd.
-noselect to prevent automatic selection activation.
-dispMode and -highMode to define displaying and highlighting modes.
-2d, -2dtopdown and -3d to manage displaying in screen coordinates.
-trsfPers and -trsfPersPos for Transformation Persistence options.
Drop command vsettransmode, replaced by vdisplay.
Correction of test-case bugs vis bug641
