2014-03-21  Christopher Faylor  <me.binutils2014@cgf.cx>

	* ld.texinfo: Document change in handling of --enable-auto-image-base.
	* emultempl/pe.em (pe_auto_image_base): Set to default base.
	(gld_${EMULATION_NAME}_list_options): Change usage message to reflect
	optional --enable-auto-image-base argument.
	(gld${EMULATION_NAME}_handle_option): Handle optional
	--enable-auto-image-base argument.
	(compute_dll_image_base): Eliminate constant.  Use pe_auto_image_base.