(image-forward-hscroll, image-backward-hscroll)

(image-forward-hscroll, image-backward-hscroll)
(image-next-line, image-previous-line, image-scroll-up)
(image-scroll-down, image-bol, image-eol, image-bob, image-eob):
New functions.
(image-mode-map): Remap motion commands.
(image-mode-text-map): New keymap for viewing images as text.
(image-mode): Use image-mode-map.
(image-toggle-display): Toggle auto-hscroll-mode and mode keymaps.