extension Makefile fragments, because they really don't have anything to
do with the buildlink[12] frameworks. Change all the Makefiles that use
application.buildlink.mk and extension.buildlink.mk to use application.mk
and extension.mk instead.
all dependencies on packages depending on "png" which contain shared
libraries, all for the (imminent) update to the "png" package.
[List courtesy of John Darrow, courtesy of "bulk-build".]
