automake 1.13 errors if AM_CONFIG_HEADER is used in configure script.
automake 1.13 no longer autoupdates AM_CONFIG_HEADER to
AC_CONFIG_HEADERS, thing which automake has been doing since automake
version 1.7

Given that our first automake supported version is automake 1.7,
simply replacing AM_CONFIG_HEADER usage with AC_CONFIG_HEADERS seems
enough to yet support same automake versions.

Dave Reisner reported issue with 1.13 and provided patch.

http://curl.haxx.se/mail/lib-2012-12/0246.html

Provide a 'traceable' AC_CONFIG_MACRO_DIR definition only when using
an autoconf version that does not provide it, instead of what we were
doing up to now of providing and overriding AC_CONFIG_MACRO_DIR for
all autoconf versions.

* Changing the order of the state machine to represent the order in
  which commands are sent to the server.

* Reworking the imap_endofresp() function as the FETCH response doesn't
  include the command id and shouldn't be part of the length comparison
  that takes into account the id string.

Applied the same debug message as used in smtp_doing() and imap_doing()
when pop3_multi_statemach() fails.

Applied the POP3 fix from commit 2897ce7d so imap_dophase_done()
isn't called if imap_multi_statemach() fails.

Applied the POP3 fix from commit 2897ce7d so smtp_dophase_done()
isn't called if smtp_multi_statemach() fails.

Removed unnecessary state changes in pop3_state_starttls_resp()
following previous fix in IMAP module.

Provided extra comments in the SMTP module following previous IMAP fix.

Fixed a problem with the state machine when attempting to log in with
invalid credentials. The server would report login failure but libcurl
would not read the response due to inappropriate IMAP_STOP states being
set after the login was sent.

Applied some of the comment and layout changes that had already been
applied to the pop3 and smtp code over the last 6 to 9 months.

This is in preparation of adding SASL based authentication.

Minor tidy up of comments and layout prior to next part of imap work.

Minor tidy up of comments and layout prior to next part of imap work.

Renamed imapsendf() to imap_sendf() to be more in keeping with the
other imap functions as well as Curl_pp_sendf() that it replaces.

76 private header files renamed to use our standard naming scheme.

This commit only does the file renaming.

----------------------------------------

  renamed:    amigaos.h -> curl_amigaos.h
  renamed:    arpa_telnet.h -> curl_arpa_telnet.h
  renamed:    asyn.h -> curl_asyn.h
  renamed:    axtls.h -> curl_axtls.h
  renamed:    bundles.h -> curl_bundles.h
  renamed:    conncache.h -> curl_conncache.h
  renamed:    connect.h -> curl_connect.h
  renamed:    content_encoding.h -> curl_content_encoding.h
  renamed:    cookie.h -> curl_cookie.h
  renamed:    cyassl.h -> curl_cyassl.h
  renamed:    dict.h -> curl_dict.h
  renamed:    easyif.h -> curl_easyif.h
  renamed:    escape.h -> curl_escape.h
  renamed:    file.h -> curl_file.h
  renamed:    fileinfo.h -> curl_fileinfo.h
  renamed:    formdata.h -> curl_formdata.h
  renamed:    ftp.h -> curl_ftp.h
  renamed:    ftplistparser.h -> curl_ftplistparser.h
  renamed:    getinfo.h -> curl_getinfo.h
  renamed:    gopher.h -> curl_gopher.h
  renamed:    gtls.h -> curl_gtls.h
  renamed:    hash.h -> curl_hash.h
  renamed:    hostcheck.h -> curl_hostcheck.h
  renamed:    hostip.h -> curl_hostip.h
  renamed:    http.h -> curl_http.h
  renamed:    http_chunks.h -> curl_http_chunks.h
  renamed:    http_digest.h -> curl_http_digest.h
  renamed:    http_negotiate.h -> curl_http_negotiate.h
  renamed:    http_proxy.h -> curl_http_proxy.h
  renamed:    if2ip.h -> curl_if2ip.h
  renamed:    imap.h -> curl_imap.h
  renamed:    inet_ntop.h -> curl_inet_ntop.h
  renamed:    inet_pton.h -> curl_inet_pton.h
  renamed:    krb4.h -> curl_krb4.h
  renamed:    llist.h -> curl_llist.h
  renamed:    memdebug.h -> curl_memdebug.h
  renamed:    multiif.h -> curl_multiif.h
  renamed:    netrc.h -> curl_netrc.h
  renamed:    non-ascii.h -> curl_non-ascii.h
  renamed:    nonblock.h -> curl_nonblock.h
  renamed:    nssg.h -> curl_nssg.h
  renamed:    parsedate.h -> curl_parsedate.h
  renamed:    pingpong.h -> curl_pingpong.h
  renamed:    polarssl.h -> curl_polarssl.h
  renamed:    pop3.h -> curl_pop3.h
  renamed:    progress.h -> curl_progress.h
  renamed:    qssl.h -> curl_qssl.h
  renamed:    rawstr.h -> curl_rawstr.h
  renamed:    rtsp.h -> curl_rtsp.h
  renamed:    select.h -> curl_select.h
  renamed:    sendf.h -> curl_sendf.h
  renamed:    setup.h -> curl_setup.h
  renamed:    setup_once.h -> curl_setup_once.h
  renamed:    share.h -> curl_share.h
  renamed:    slist.h -> curl_slist.h
  renamed:    smtp.h -> curl_smtp.h
  renamed:    sockaddr.h -> curl_sockaddr.h
  renamed:    socks.h -> curl_socks.h
  renamed:    speedcheck.h -> curl_speedcheck.h
  renamed:    splay.h -> curl_splay.h
  renamed:    ssh.h -> curl_ssh.h
  renamed:    sslgen.h -> curl_sslgen.h
  renamed:    ssluse.h -> curl_ssluse.h
  renamed:    strdup.h -> curl_strdup.h
  renamed:    strequal.h -> curl_strequal.h
  renamed:    strerror.h -> curl_strerror.h
  renamed:    strtok.h -> curl_strtok.h
  renamed:    strtoofft.h -> curl_strtoofft.h
  renamed:    telnet.h -> curl_telnet.h
  renamed:    tftp.h -> curl_tftp.h
  renamed:    timeval.h -> curl_timeval.h
  renamed:    transfer.h -> curl_transfer.h
  renamed:    url.h -> curl_url.h
  renamed:    urldata.h -> curl_urldata.h
  renamed:    warnless.h -> curl_warnless.h
  renamed:    wildcard.h -> curl_wildcard.h

----------------------------------------

76 private header files renamed to use our standard naming scheme.

This change affects 322 files in libcurl's source tree.

Fixed a problem with sending usernames and passwords that contain
backslash, quotation mark and space characters.

... on Snow Leopard and Lion

Snow Leopard introduced the SSLSetSessionOption() function, but it
doesn't disable peer verification as expected on Snow Leopard or
Lion (it works as expected in Mountain Lion). So we now use sysctl()
to detect whether or not the user is using Snow Leopard or Lion,
and if that's the case, then we now use the deprecated
SSLSetEnableCertVerify() function instead to disable peer verification.

WinSock select() does not support standard file descriptors,
it can only check SOCKETs. The following function is an attempt
to create a select() function with support for other handles.

... and have it take a proper 'struct connectdata *' as first argument

... it also clobbered the 'result' return value so that it wouldn't
return the error back to the parent function properly, which broke test
809 when run with 'multi-always'.