#15 Selecting "No" for changed preferences should revert

[Christian Hujer]

When preferences are changed (prefs.isChanged()) and another preferences module is selected, a dialog is displayed that asks the user whether or not to apply the changes or cancel the selection.

For cancel, everything works fine. The selection is cancelled and the current preferences stay selected.
For yes, everything works fine. The current preferences are applied and the new preferences get selected.

For no, the current preferences are not applied and the new preferences get selected. The expected behaviour would be, reselecting the current preferences, to see their stored state. In fact, their last modified state is shown. Therefore, for no revert() should be called.