Fix handling of local variables in GO routine
Allow "OPT" and "AUX" variables in V6 GO routines, and give better diagnostic messages for the disallowed cases (required arguments in V6; any local variables in other versions). Fixes ZILF-210.
This instance will be upgraded to Heptapod 0.21.0 (final) on 2021-04-23 at 10:30 UTC+2 (a few minutes of down time)
Allow "OPT" and "AUX" variables in V6 GO routines, and give better diagnostic messages for the disallowed cases (required arguments in V6; any local variables in other versions). Fixes ZILF-210.