2003-10-27  Alan Mackenzie  <acm@muc.de>

	Add changes to allow scrolling whilst in isearch mode:

	* isearch.el:
	(isearch-unread-key-sequence): New function, extracted from
	isearch-other-meta-char.
	(put 'foo 'isearch-scroll) on all Emacs's "scrollable" standard
	functions.
	(isearch-allow-scroll): New customizable variable.
	(isearch-string-out-of-window): New function.
	(isearch-back-into-window): New function.
	(isearch-reread-key-sequence-naturally): New function.
	(isearch-lookup-scroll-key): New function.
	(isearch-other-meta-char): Doc string and functionality enhanced.
	Now accepts a prefix argument.
	(isearch-lazy-highlight-window-end): New variable.
	(isearch-lazy-highlight-new-loop): Minor enhancements.
	
	* simple.el:
	(overriding-map-is-bound, saved-overriding-map): New variables.
	(ensure-overriding-map-is-bound, restore-overriding-map): New
	functions.
	(universal-argument, universal-argument-more, negative-argument,
	digit-argument, universal-argument-other-key): Minor changes.