Before this patch we always relied on dunecontrol/pkg-config to check
for the correct version. With this patch we include this functionality
also when building packges with dunecontrol for this use part of the version
checking of cmake (or pkg-config if there are packages without CMake support).
Basically we let CMake check wether the major and minor version matches and
afterwards use the information from the dune.module file. This should make
it possible to have several versions of DUNE installed and still always use
the correct version. During fixing these issues we noticed that our version
files were not recognized because the carried the wrong name. Now we use the
correct name <dune-module>-config-version.cmake.