Added a new property to the menu object, ampersandHotkeysInItems, which...

Added a new property to the menu object, ampersandHotkeysInItems, which specifies whether or not to interpret an ampersand as a hotkey in a menu item if placed immediately before a non-space character.  It defaults to true.  In some cases it might be desirable to disable that and have all ampersands in the menu items literally displayed.