Reorganize code slightly, and add comment to CONVERT-FUNCTION.
Reorganize code slightly, and add comment to CONVERT-FUNCTION.

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