[RELEASE] Released version 2.5.3

[RELEASE] Released version 2.5.3

Released version 2.5.3 with the following main changes :
    - MINOR: sock: move the unused socket cleaning code into its own function
    - BUG/MEDIUM: mworker: close unused transferred FDs on load failure
    - BUG/MINOR: mworker: fix a FD leak of a sockpair upon a failed reload
    - BUG/MINOR: sink: Use the right field in appctx context in release callback
    - BUG/MEDIUM: resolvers: Really ignore trailing dot in domain names
    - BUG/MEDIUM: fd: always align fdtab[] to 64 bytes
    - BUG/MAJOR: compiler: relax alignment constraints on certain structures
    - MINOR: httpclient: Don't limit data transfer to 1024 bytes
    - BUG/MINOR: httpclient: reinit flags in httpclient_start()
    - BUG/MINOR: mailers: negotiate SMTP, not ESMTP
    - BUG/MINOR: ssl: Add missing return value check in ssl_ocsp_response_print
    - BUG/MINOR: ssl: Fix leak in "show ssl ocsp-response" CLI command
    - BUG/MINOR: ssl: Missing return value check in ssl_ocsp_response_print
    - CLEANUP: httpclient/cli: fix indentation alignment of the help message
    - BUG/MINOR: tools: url2sa reads ipv4 too far
    - BUG/MEDIUM: httpclient: limit transfers to the maximum available room
    - DEBUG: buffer: check in __b_put_blk() whether the buffer room is respected