Now that warnings were almost all removed, let's enable zero-warning
via -dW. All tests were adjusted, but two:
- mcli/mcli_start_progs.vtc:
the programs section currently cannot be silenced
- stats/stats-file.vtc:
the warning comes from the stats file itself on comment lines.
All other ones are now OK.
The new global keywords "http-err-codes" and "http-fail-codes" allow to
redefine which HTTP status codes indicate a client-induced error or a
server error, as tracked by stick-table counters. This is only done
globally, though everything was done so that it could easily be extended
to a per-proxy mechanism if there was a real need for this (but it would
eat quite more RAM then).
A simple reg-test was added (http-err-fail.vtc).
