Added the following colon commands. (At present, you must type the colon explicitly):
  :e! Revert all changes to a .leo file, prompting if there have been changes.
  :q Quit, prompting for saves.
  :qa Quit only if there are no unsaved changes.
  :w Save the .leo file.
  :wa Save all changed  .leo files.
  :wq Save all open files and exit.
  :xa ave all open files and exit.