Re-add alarm(2) calls around the calls to fetchStat(3) and fetchXGet(3),
since these calls can still time out on DNS lookups or TCP connect(2).
Remove the alarm(2) calls in the main loop, since all methods properly
handle transfer timeouts (as opposed to connection timeouts).
Set the sigalrm flag if a timeout occurs in the main loop.
Move the signal: label up a little so we still set the atime and mtime
when the transfer times out or is interrupted, so that restarted transfers
will work as expected (as long as the file still exists).
MFC after: 2 weeks
dc161d5582