edit-menu:between-find-and-preferences in drscheme:frame:basics-mixin

This method is called between the addition of the find menu-item and before the addition of the preferences menu-item to the edit-menu menu. Override it to add additional menus at that point.

• (send a-drscheme:frame:basics-mixin edit-menu:between-find-and-preferences void

  Adds a separator-menu-item%. Next, adds the "Keybindings" menu item to the edit menu. Finally, if the current-eventspace-has-standard-menus? procedure returns #f, creates another separator-menu-item%.