Use child data source's color map when available
Use child data source's color map when available

In the Rotate Align Widget, use a child data source's color
map when it is available so that the color map will match
that of the view.

Signed-off-by: Patrick Avery <743342299f279e7a8c3ff5eb40671fce3e95f13a@kitware.com>

OpenChemistry/tomviz,OpenChemistry/tomviz,OpenChemistry/tomviz,OpenChemistry/tomviz