bincopyfrom: write trailing newline after error
bincopyfrom: write trailing newline after error

Help Python not crashing because of generating a 6G long string.  A bit
silly, but ok, the newline was forgotten.

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