LockRow — Sets lock/authorization for a row in a table.
integer LockRow(text  a_schema_name, text  a_table_name, text  a_row_key, text an_auth_token, timestamp expire_dt);
integer LockRow(text  a_table_name, text  a_row_key, text an_auth_token, timestamp expire_dt);
integer LockRow(text  a_table_name, text  a_row_key, text an_auth_token);
Sets lock/authorization for a specific row in a table.
		an_auth_token is a text value.
		expire_dt is a timestamp
		which defaults to now() + 1 hour.
		Returns 1 if lock has been assigned, 0
		otherwise (i.e. row is already locked by another auth.)
Availability: 1.1.3