When launching a visualizer, no longer store an Operation

The target is to have less Operation rows, as well as to simplify the flow on launching a visualizer.
Possibly have a new flow for launching a viewer, as first step. Use this new flow in all required places (launching viewers from dataType overlay; portlets). Once these will function correctly, we could perhaps cleanup the current launch procedure (used both for regular ops and viewers).
This will probably involve refactor in ABCDisplayer class.