A patch documenting behaviour for omitted optional arguments in
`forward-char', `backward-char' and `forward-line' follows. While it's
clear from context, one could also change "Move N lines/characters" to
"Move abs(N) lines/characters" to be precise. ChangeLog:

2006-11-13  Markus Triska  <triska@gmx.at>

	* cmds.c (backward-char, forward-char, forward-line): Document
	behaviour for omitted optional arguments