only emit a message and don't actually fetch anything. This allows
us to make the output of "fetch-list" for these packages consistent
with other packages.
While we're in here, integrate DYNAMIC_MASTER_SITES with the
${ORDERED_SITES} macro. The only functional change here is that
${MASTER_SITE_OVERRIDE} is now respected. Still to do -- something
appropriate for "fetch-list" for these packages, like sourcing
"getsites.sh" into the generated script. (Well, "package", but there
are two others that do something similar in their "Makefile".)
Also eliminate the misbegotten _FETCH_ALLFILES macro -- now that only
"fetch" uses it, move it's functionality directly under "do-fetch".
