* app/core/gimpimage-arrange.[ch]: added, utility function for
	aligning and arranging things in an image.

	* app/core/gimpitem-align.[ch}: removed, no longer needed.

	* app/core/gimpimage-item-list.[ch] (gimp_image_item_list_align):
	removed this function, no longer used.

	* app/core/Makefile.am: changes described above.

	* app/core/gimpguide.c: remove bit of cruft left accidentally.

	* app/tools/gimpalignoptions.[ch]: remove "alignment type"
	option, not needed at this point.

	* app/tools/gimpaligntool.[ch]: numerous changes, most
	importantly ability to align guides, and use them for
	alignment.  More work coming on this tool.