Fixes bugs #314, #324, and #325.

	* components/help/hyperbola.goad:
	Corrected repo_ids -> repo_id, reported by Richard Hult.

	* src/nautilus.goad:
	Added missing = character, reported by Richard Hult.

	* libnautilus/gnome-icon-container-grid.c:
	* libnautilus/gnome-icon-container-grid.h:
	* libnautilus/gnome-icon-container.c:
	* libnautilus/gnome-icon-container-private.h:
	Made the icon grid handle negative coordinates.
	Removed most of the icon grid code.
	Reimplemented the arrow keys. They should work again.

	* libnautilus/nautilus-gnome-extensions.c:
	* libnautilus/nautilus-gnome-extensions.h:
	(nautilus_art_irect_contains_irect):
	Added another helper function.

	* libnautilus/nautilus-icons-view-icon-item.c:

	* libnautilus/nautilus-icons-view-icon-item.h:
	* libnautilus/gnome-icon-container.c:
	* libnautilus/gnome-icon-container-private.h:
	Added user data to each canvas item and got rid of the hash table
	that maps canvas items to icons.

	* RENAMING: Tweaks.