Store UI-settings of Eclipse SWT PFGrid
Use the methods loadSettings(IDialogSettings) and saveSettings() : IDialogSettings in order
to persist settings of the PFGrid.
Settings changed by the user like column-width, column-visibility, grouping, sorting etc. can be persisted
by using the JFace-IDialogSettings.
The UI-settings could be persisted in the disposeListener of the grid and restored when the UI is created.