Added axTLS to autotool files and glue code to misc other files.
axtls.h maps SSL API functions, but may change.
axtls.c is just a stub file and will definitely change.

The function that checks if pipelining is possible now requires the HTTP
bit to be set so that it doesn't mistakenly tries to do it for other
protocols.

Bug: http://curl.haxx.se/mail/lib-2010-12/0152.html
Reported by: Dmitri Shubin

The generic timeout code must not check easy handles that are already
completed. Going to completed (again) within there risked decreasing the
number of alive handles again and thus it could go negative.

This regression bug was added in 7.21.2 in commit ca10e28f

Cleanup fix after Kamil's commit 5c7c9a76

ossl_connect_common() now checks whether or not 'struct
connectdata->state' is equal 'ssl_connection_complete' and if so, will
return CURLE_OK with 'done' set to 'TRUE'. This check prevents
ossl_connect_common() from creating a new ssl connection on an existing
ssl session which causes openssl to fail when it tries to parse an
encrypted TLS packet since the cipher data was effectively thrown away
when the new ssl connection was created.

Bug: http://curl.haxx.se/mail/lib-2010-11/0169.html

It helps to prevent a hangup with some FTP servers in case idle session
timeout has exceeded.  But it may be useful also for other protocols
that send any quit message on disconnect.  Currently used by FTP, POP3,
IMAP and SMTP.

When looping in this function and checking for the timeout being
expired, it was not updating the reference time when calculating the
timediff since previous round which made it think each subsequent loop
to have taken longer than it actually did.

I also modified the function to use the generic Curl_timeleft() function
instead of the custom logic.

Bug: http://curl.haxx.se/bug/view.cgi?id=3112579

When send() and recv() fail, we now store the errno value to allow the
app to access it.

Bug: http://curl.haxx.se/bug/view.cgi?id=3128121
Reported by: Yuri

- Show address string from proper buffer in case of connection failure.

- Try next address when inet_ntop() fails.

Reinstate IPV6 build variable that got removed.

Failed to commit this file changes along with the others.

warning C4146: unary minus operator applied to unsigned type, result still unsigned

Ensure that spurious results from system's getaddrinfo() ares not propagated
by Curl_getaddrinfo_ex() into the library.

Also ensure that the ai_addrlen member of Curl_getaddrinfo_ex()'s output linked
list of Curl_addrinfo structures has appropriate family-specific address size.

... not the proxy port.  It makes no difference unless a proxy is used.