GasLiftGroupInfo.cpp did not include "config.h" which caused HAVE_MPI
to be undefined causing the file to be compiled with
Dune::Communication<No_Comm> instead of with
Dune::Communication<MPI_Comm>. Which later caused linking problems with files
that used MPI.
Check group limits in gas lift stage 1 to avoid adding too much ALQ which must
anyway later be removed in stage 2. This should make the optimization
more efficient for small ALQ increment values. Also adds MPI support.
