Add visual indicator for batch mode operators

[BrentOzar]

Niko "Columnstore" Neugebauer had a great idea: when an operator is working in batch mode, add a small icon of a lightning bolt in the top right corner, over the iterator icon, kinda like how parallelism shows in an execution plan. Would this be doable?

[JustinPealing]

Nice, I shall take a look!

[JustinPealing]

For reference, Twitter conversation:
https://twitter.com/NikoNeugebauer/status/1047789359137738754

Microsoft Feedback:
https://feedback.azure.com/forums/908035-sql-server/suggestions/32901922-improve-visual-analysis-of-the-columnstore-indexes

[JustinPealing]

First attempt:

[JustinPealing]

OK, so if the Actual Execution Mode is present, that is used to work out whether or not to show the lighting icon, otherwise the Estimated Execution Mode is used.