Log Message:
Update to 0.17.1.  Bugfixes in library (some bugs introduced in 0.17):

	- 0000560: [xmp] Can't delete (last) XMP tag. (Reported by SerGioGioGio)

	- 0000559: [exif] Crash when extracting Exif orientation flag
	           from Kodak DCR raw file. (Reported by Gilles Caulier)

	- 0000558: [jpeg i/o] "Warning: JPEG format error, rc = 5" for
	           most of my JPEG files. (Reported with patch by
	           Marcus Holland-Moritz)

	- 0000552: [build environment] Build failure under Mac OS X
	           10.3.9 (Reported by Marius Schamschula)

	- [exif] Fixed several potential division by 0 bugs.