imitate other controls like DropDownButton, etc.
 * rework several main toolbar items to use fox.form.Select instead of
other controls
 * replace HOOK_HEADLINE_TOOLBAR_SELECT_MENU_ITEM with
HOOK_HEADLINE_TOOLBAR_SELECT_MENU_ITEM2 because of markup change (option
instead of menuitem)
 * PluginHost: add some explicit typecasts to make intellephense shut up