These test files were apparently designed to expect external index

These test files were apparently designed to expect external index
files that get generated by the DSSSL build. But the XSL build
does not generate them, and, when it finds them missing, the build
breaks. So, commented out the DSSSL stuff and added <index/>
instances. If you want to test these files with DSSSL output, you
will need to uncomment the entity refs at the end.