Added test for FROM - DOWNTO clauses with NIL variable and side effect.
Added test for FROM - DOWNTO clauses with NIL variable and side effect.

clasp-developers/SICL,clasp-developers/SICL,clasp-developers/SICL,vtomole/SICL,clasp-developers/SICL,vtomole/SICL,vtomole/SICL,vtomole/SICL