* Pass LIBfoo_VERSION environment variables like it's done for simple and
gnu configure scripts. This unbreaks generating CMake config files
in the upcoming Qt 5.6.2.
* Don't call -recursive for Qt3's qmake, it doesn't support this flag.
This removes support of separate qmake versions in one port: as we
discovered, there are no ports actually needing this; strangers like
print/poppler don't use qmake in build.
This should be transparent to current ports. But expect more tweaks there:
for now, qt?.port.mk forces qmake.port.mk inclusion, but that will be
reworked to a more common scheme.
Same idea from (at least) espie@ and me; also, espie@ agrees on the plan.
