[Emacs-ada-mode] Imenu support

[Simon Wright]

In ada-mode.html, in the Customizing ... section, you recommend

  (global-font-lock-mode t)
  (transient-mark-mode t)

I find Imenu very helpful .. (originally from glide.el)

  (require 'imenu)
  (setq imenu-auto-rescan t)   ;;; set to t if we should always rescan
  (setq imenu-use-markers nil) ;;; if we automatically rescan, use positions
  (set 'imenu-scanning-message nil) ;;; no message should be displayed
  (add-hook 'ada-mode-hook (lambda() (imenu-add-to-menubar "Entities")))