CompoundEditor : Highlight editors to preview linking relationships
CompoundEditor : Highlight editors to preview linking relationships

User facing changes

 - Items in the CompoundEditor pinning menu that link editors together now
   highlight the target editor when they are hovered. This helps
   disambiguate which editor will be user as master when multiple editors
   of the same type are present in the layout.

GafferHQ/gaffer,ImageEngine/gaffer,boberfly/gaffer,johnhaddon/gaffer,hradec/gaffer,boberfly/gaffer,andrewkaufman/gaffer,ImageEngine/gaffer,johnhaddon/gaffer,lucienfostier/gaffer,appleseedhq/gaffer,lucienfostier/gaffer,hradec/gaffer,johnhaddon/gaffer,andrewkaufman/gaffer,appleseedhq/gaffer,GafferHQ/gaffer,johnhaddon/gaffer,appleseedhq/gaffer,lucienfostier/gaffer,hradec/gaffer,ImageEngine/gaffer,lucienfostier/gaffer,GafferHQ/gaffer,andrewkaufman/gaffer,ImageEngine/gaffer,GafferHQ/gaffer,hradec/gaffer,appleseedhq/gaffer,andrewkaufman/gaffer,johnhaddon/gaffer,boberfly/gaffer,GafferHQ/gaffer,hradec/gaffer,boberfly/gaffer,andrewkaufman/gaffer