db_multirow: fall back to -local behavior, when used outside of an ADP file
The old behavior was, that when "db_multirow" was called outside an ADP environment, an error was generated, since the uplevel was determined without the "-local" flag by [template::adp_level]. Outside ADP, the result of the function is empty, leading to an error that a level "#" is invalid. Depending on an optional flag is strange for a "db_*" command.
Now, the default behavior outside ADP file is local (i.e., when calling outside ADP, the output variables are set in the calling scope, unless a different "upvar_level" is specified).