Multiple selection doesn’t work in 'execution monitor'

[sandepat]

Issue

1. When multiple executions are selected, none of the operations work on all of them simultaneously. (e.g clean execution, purge execution)
2. Could be useful to perform simultaneous operations.

Relevant classes

1. SimulationToolStrip
2. SimulationContexMenu

[axlbonnet]

This is not easy because currently selection is mean to be used with the buttons on top of the grid, although the right-click context is meant to be used on the single execution of the click (and only this one).
As you experienced it, you expected the right-click context to also be used on the current selection and i get that.
However the, the right-click context options are dependent of the status of the execution (like kill/clean), so if several executions with different status are selected, what options should be displayed ? Also, an option like "relaunch" is not meant in my opinion to be used on many executions.
I think we should keep the current behavior, use the top buttons for "batch" operation, and right-click for specific operation, but make it clear it won't apply to a selection if there is one.