Merge branch 'remove-ugtime' into 'master'

dune/uggrid/domain/std_domain.cc

dune/uggrid/gm/er.cc

dune/uggrid/gm/evm.cc

dune/uggrid/gm/evm.h

dune/uggrid/gm/gm.h

dune/uggrid/gm/refine.cc

dune/uggrid/gm/rm.cc

dune/uggrid/gm/shapes.cc

dune/uggrid/gm/ugio.cc

dune/uggrid/gm/ugm.cc

dune/uggrid/low/CMakeLists.txt

dune/uggrid/low/fileopen.cc

dune/uggrid/low/fileopen.h

dune/uggrid/low/misc.cc

dune/uggrid/low/misc.h

dune/uggrid/low/ugtime.h

dune/uggrid/low/ugtimer.cc

dune/uggrid/low/ugtimer.h

dune/uggrid/parallel/dddif/overlap.cc

dune/uggrid/parallel/dddif/trans.cc