improved filtering/normalization of file/path names in usage messages (mainly) in case tests are run via `make check` / `sh RunMtest`
improved filtering/normalization of file/path names in usage messages
(mainly) in case tests are run via `make check` / `sh RunMtest`

zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb