Specifies the short cuts (in addition to ShortCut) for triggering clients.
Actions can execute in response to multiple short cut key combinations. SecondaryShortCuts lists all the short cut key combinations (other than the one specified by the ShortCut property) that can trigger the action. This lets you specify shortcuts for clients that do not have a ShortCut property or provide additional, secondary shortcuts.
When the user types one of the key combinations listed in SecondaryShortCuts, the action's DoExecute method is called.