fixed bug #78501 when using a non ascii character for the number

* libxslt/numbers.c libxslt/numbersInternals.h libxslt/xsltutils.[ch]:
  fixed bug #78501 when using a non ascii character for the
  number formatting grouping separator.
* tests/docs/Makefile.am tests/docs/bug-95.xml
  tests/general/Makefile.am tests/general/bug-95.*: added the
  example in the regression tests for this case
* libxslt/attributes.c: cleaning up a problem introduced in last
  patch
Daniel