[RELEASE] Released version 3.1.1

[RELEASE] Released version 3.1.1

Released version 3.1.1 with the following main changes :
    - BUG/MEDIUM: sock: Remove FD_POLL_HUP during connect() if FD_POLL_ERR is not set
    - MINOR: proxy: Add support of 421-Misdirected-Request in retry-on status
    - BUG/MINOR: log: fix lf_text() behavior with empty string
    - BUG/MINOR: improve BBR throughput on very fast links
    - BUG/MEDIUM: event_hdl: fix uninitialized value in async mode when no data is provided
    - BUG/MEDIUM: quic: prevent stream freeze on pacing
    - BUG/MEDIUM: http-ana: Reset request flag about data sent to perform a L7 retry
    - BUG/MINOR: h1-htx: Use default reason if not set when formatting the response
    - BUILD: quic: fix a build error about an non initialized timestamp
    - BUG/MINOR: signal: register default handler for SIGINT in signal_init()
    - BUG/MINOR: startup: close pidfd and free global.pidfile in handle_pidfile()
    - BUG/MINOR: startup: fix pidfile creation
    - BUG/MINOR: quic: fix bbr_inflight() calls with wrong gain value
    - BUG/MEDIUM: init: make sure only daemonized processes change their session
    - BUG/MINOR: init: do not call fork_poller() for non-forked processes
    - BUG/MEDIUM: mux-quic: remove pacing status when everything is sent
    - BUG/MINOR: quic: remove startup alert if conn socket-owner unsupported
    - BUG/MINOR: quic: remove startup alert if GSO unsupported
    - BUG/MEDIUM: mux-h2: make sure not to touch dummy streams when sending WU
    - BUG/MINOR: config: Fix parsing of accept-invalid-http-{request,response}
    - DOC: config: fix confusing init-state examples
    - BUG/MINOR: debug: COUNT_IF() should return true/false
    - BUILD: debug: fix build issues in COUNT_IF() with -Wunused-value
    - MINOR: mux-h2/traces: add a missing trace on negative initial window size
    - CLEANUP: mux-h2/traces: reword certain ambiguous traces
    - MINOR: mux-h2/glitches: add a description to the H2 glitches
    - BUG/MINOR: mux-h2: fix expression when detecting excess of CONTINUATION frames
    - BUG/MINOR: mworker: don't save program PIDs in oldpids
    - BUG/MINOR: mworker: fix -D -W -sf/-st modes
    - BUG/MINOR: startup: fix error path for master, if can't open pidfile
    - BUG/MEDIUM: startup: don't daemonize if started with -c
    - BUG/MEDIUM: startup: report status if daemonized process fails
    - BUG/MEDIUM: mworker: report status, if daemonized master fails
    - BUG/MINOR: namespace: handle a possible strdup() failure
    - BUG/MINOR: ssl_crtlist: handle a possible strdup() failure
    - BUG/MINOR: resolvers: handle a possible strdup() failure
    - BUG/MINOR: stats: decrement srv refcount on stats-file release
    - MINOR: list: define a watcher type
    - BUG/MEDIUM: stats/server: use watcher to track server during stats dump
    - BUG/MINOR: http-fetch: Ignore empty argument string for query()
    - BUG/MINOR: server-state: Fix expiration date of srvrq_check tasks
    - BUG/MINOR: hlua_fcn: restore server pairs iterator pointer consistency