someweb.com is a real registrable domain; example.com is reserved for
documentation (RFC 2606). Replace it across the HTML guides, the CLI
--help text (htshelp.c) and code comments, then regenerate man/httrack.1
and the rendered html/httrack.man.html. Other placeholder domains are
left alone: they appear inside filter/wildcard examples where the host
interacts with the pattern.