Bug: https://github.com/bagder/curl/pull/157

The code used some happy eyeballs logic even _after_ CONNECT has been
sent to a proxy, while the happy eyeball phase is already (should be)
over by then.

This is solved by splitting the multi state into two separate states
introducing the new SENDPROTOCONNECT state.

Bug: http://curl.haxx.se/mail/lib-2015-01/0170.html
Reported-by: Peter Laser

Since they already exist and will make comparing easier

malloc() and strdup() calls without checking return codes.

Reported-by: Markus Elfring
Bug: https://github.com/bagder/curl/issues/150

Reported-by: Jonathan Cardoso

In addition to commit 709cf76f, removed the USE_SSLEAY preprocessor
variable from the Visual Studio project files as it isn't required
anymore.

Since 1342a96e, a timeout detected in the multi state machine didn't
necesarily clear everything up, like formpost data.

Bug: https://github.com/bagder/curl/issues/147
Reported-by: Michel Promonet
Patched-by: Michel Promonet

OpenSSL handling was a little broken.

SSLeay was the name of the library that was subsequently turned into
OpenSSL many moons ago (1999). curl does not work with the old SSLeay
library since years. This is now reflected by only using USE_OPENSSL in
code that depends on OpenSSL.

Acked-by: Brad King

... which otherwise made the script skip the _LAST define for some
symbols.

Reported-by: Jeroen Ooms
Bug: http://curl.haxx.se/mail/lib-2015-03/0052.html

Reported-by: Jon Seymour

No need to use _MPRINTF_REPLACE internally.

Bug: https://github.com/bagder/curl/pull/144

... and as a consequence, introduce curl_printf.h with that re-define
magic instead and make all libcurl code use that instead.

And UTF8-fix a few names

Reported-by: Jonathan Cardoso

Reporte-by: Steve Havelka

... to avoid a build failure when configured with --enable-debug

Previously, we just ignored error code passed to
on_stream_close_callback and just return 0 (success) after stream
closure even if stream was reset with error.  This patch records error
code in on_stream_close_callback, and return -1 and use CURLE_HTTP2
error code on abnormal stream closure.