hgweb: run with "served" filter
This changeset enable the "served" filter on all repo used by hgweb.
Hgweb misbehave in a lot of when filtering changeset are present but I do not
expect normal people to have secret or obsolete changeset on they server.
Misbehavior will be gradually fixed later.
$ echo 'raise Exception("bit bucket overflow")' > badext.py
$ abspath=`pwd`/badext.py
$ echo '[extensions]' >> $HGRCPATH
$ echo "gpg =" >> $HGRCPATH
$ echo "hgext.gpg =" >> $HGRCPATH
$ echo "badext = $abspath" >> $HGRCPATH
$ echo "badext2 =" >> $HGRCPATH
$ hg -q help help
*** failed to import extension badext from $TESTTMP/badext.py: bit bucket overflow
*** failed to import extension badext2: No module named badext2
hg help [-ec] [TOPIC]
show help for a given topic or a help overview