monetdb: return 1 if starting/stopping one (or more) databases failed
monetdb: return 1 if starting/stopping one (or more) databases failed

For scripts, adhere to the policy mandated by the manpage and common
sense that we return 1 when the operation failed.

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