#37 xsieve's -o option seems not to work

[Reuben Thomas]

xsieve -o output_file xsieve_xslt_file xml_file

is the given syntax, but if I use it, I still get the
output on the terminal. If I just do

xsieve xsieve_xslt_file xml_file > output_file

then it works fine, so it's not really a complaint
about xsieve, but more about the documentation.

Using XSieve 1.1.0 built myself on Linux (Debian/etch).