BUG: #3438 Avoid hang when saving due to non-visible widget grab

If the OpenGL context of the window is not correctly initialized,
then VTK cannot get a copy of the pixels and goes into an
infinite loop checking the GL error.  This CTK version includes
a patch from Andras avoids this problem.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22605 3bd1e089-480b-0410-8dfb-8563597acbee
BUG: see comment in r17038 of slicer3 trunk

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22606 3bd1e089-480b-0410-8dfb-8563597acbee
BUG: Read vectors as scalars

3-vectors were read as Vectors and placed on PointData.
All other vector lengths are read as multi-component Scalars
on PointData.

This patch treats all vectors as scalars to be consistent.

git-svn-id: http://svn.slicer.org/Slicer4/trunk@22607 3bd1e089-480b-0410-8dfb-8563597acbee
ENH: add copy to markups list right click option

Can now right click on a markup in the GUI and copy it
to another list, placing it at the end of the destination
list.
Updated the right click Move option to only offer at the
end of the list as that simplifies the UI and users can
move the markups with the move up/down buttons.
Updated test for logic copy.
Updated documentation for copy.

Issue #3397



git-svn-id: http://svn.slicer.org/Slicer4/trunk@22608 3bd1e089-480b-0410-8dfb-8563597acbee
STYLE: updated tool tip for markups table

Add a tool tip to hint at the right click context menu.

Issue #3397



git-svn-id: http://svn.slicer.org/Slicer4/trunk@22609 3bd1e089-480b-0410-8dfb-8563597acbee