Make a new map by make-keymap.

Make a new map by make-keymap.
(picture-desired-column): New variable.
(picture-update-desired-column): New function.
(picture-beginning-of-line): Set picture-desired-column to 0.
(picture-end-of-line): Set picture-desired-column to the current
column.
(picture-forward-column): Pay attention to multi-column character.
(picture-backward-column): Likewise.
(picture-move-down): Likewise.
(picture-move-up): Likewise.
(picture-movement-nw): With prefix arg, move twice columns.
(picture-movement-ne): Likewise.
(picture-movement-sw): Likewise.
(picture-movement-se): Likewise.
(picture-set-motion): Handle two-column movements.
(picture-move): Call picture-move-down or picture-forward-column
only when necessary.
(picture-insert): Pay attention to picture-desired-column.
(picture-self-insert): Likewise.
(picture-clear-column): Pay attention to multi-column character.
(picture-mode): Modify doc-string for two-column movement.