Consolidated the SimulationEditDialog and SimulationPlotExportDialog
into a single dialog which uses CardLayout to switch between contents.
The new SimulationEditDialog is pretty smart about when it can support
the plot view and continues to support multi-edit.  Double-click in the
SimulationPanel is a little smarter - it opens either the dialog in plot
mode when appropriate.  Fixed but in SimulationPanel where the status
icon was not updated after running a simulation when plot button is
pressed.