WRKSRC. LIBTOOL_OVERRIDE defaults to "libtool */libtool and */*/libtool,"
meaning that, in most packages, there's no need to set it.
So: Nuke tons of LIBTOOL_OVERRIDE=${WRKSRC} and adjust a few
SHLIBTOOL_OVERRIDEs (remove ${WRKSRC} from them).
libxml++ is a C++ interface for working with XML files. It uses libxml2
to parse and write the actual XML files. It has a simple and complete API.
(I packaged this so I can now build Passepartout which I am also packaging.)