Fix NodeUI documentation:url metadata.
Fix NodeUI documentation:url metadata.

The file structure of the docs was re-organized a while back, but we forgot to update these links.

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