changes in implicit velocity output: works now also with branched grids and...

changes in implicit velocity output: works now also with branched grids and withgrids where dim != dimworld

reviewed by Bernd



git-svn-id: svn://svn.iws.uni-stuttgart.de/DUMUX/dumux/trunk@14065 2fb0f335-1f38-0410-981e-8018bf24f1b0