Ignore executable 'dune_wzl_compare'
Fix program names in the help messages
Hard-wire missing hdf5 C++ libraries to the linker flags

The auto-tools test for hdf5 does not find them.
Also build dune_wzl_compare when building with the AutoTools
Use method leafGridView instead of leafView

The latter is deprecated and produces warnings.
Call MPIHelper::instance at the beginning of the main method

This is necessary when linking against an MPI-enabled dune-common.
One such case is the dune-common package in Debian experimental.
Switch off iterative refinement

Makes the back-solving _much_ faster, without leading to a noticeable
decrease in accuracy.
Print help text when input or output file names are missing