Added special version of NSTRING-UPCASE valid for simple strings.
Added special version of NSTRING-UPCASE valid for simple strings.

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