Porters: please make sure you use bsd.port.mk 1.75 or later when
updating ports. That version of the makefile adds all sums. Previous
versions of the makefile will still work for people installing ports.
version was left at 1.0. Oops. The old tiff (3.3) installed as
libtiff.so.3.3. Install tiff34 as libtiff.so.3.4 but keep the libtiff34
link at version 1.0. confusing but it seems to work correctly.
Update all ports that depend upon tiff so the dependency is on
tiff.3.4.