merge of trunk with arhfile2 branch: 'using namespace' removed from header...
merge of trunk with arhfile2 branch: 'using namespace' removed from header files, file readers/writer moved to subnamespace AMDiS::io, test for arh2writer added
merge of trunk with arhfile2 branch: 'using namespace' removed from header files, file readers/writer moved to subnamespace AMDiS::io, test for arh2writer added