We compiled XFCE4 debs from Jessie source for use on Wheezy, as Wheezy's
version was too old for some reason (I can't remember the details).

Some manual fixups were needed:

- Had to add -fPIC to CFLAGS
- Generated libtool died with syntax error, I replaced it with a link to
  /usr/bin/libtool
- debian/libxfce4util-dev.install was missing the pattern usr/lib/*/lib*.a
- ditto debian/libxfconf-0-dev.install
- ditto libxfce4ui-1-dev.install