sync'ed lowrank branch with trunk

dune/solvers/common/staticmatrixtools.hh

dune/solvers/iterationsteps/Makefile.am

dune/solvers/iterationsteps/blockgsstep.hh

dune/solvers/iterationsteps/lineariterationstep.hh

dune/solvers/iterationsteps/mmgstep.cc

dune/solvers/iterationsteps/multigridstep.cc

dune/solvers/iterationsteps/multigridstep.hh

dune/solvers/iterationsteps/obstacletnnmgstep.hh

dune/solvers/iterationsteps/projectedblockgsstep.cc

dune/solvers/iterationsteps/projectedblockgsstep.hh

dune/solvers/iterationsteps/truncatedblockgsstep.hh

dune/solvers/iterationsteps/trustregiongsstep.cc

dune/solvers/norms/diagnorm.hh

dune/solvers/norms/fullnorm.hh

dune/solvers/solvers/solver.hh

dune/solvers/test/Makefile.am

dune/solvers/test/common.hh

dune/solvers/test/obstacletnnmgtest.cc

dune/solvers/transferoperators/genericmultigridtransfer.hh

dune/solvers/transferoperators/mandelobsrestrictor.cc