Adds access to the effectively used http version to both libcurl and
curl.

Closes #799

With OPENSSL_NO_COMP defined, there is no function
SSL_COMP_free_compression_methods

Closes #836

Fixes #828

Closes #834

Inspiration provided by: Daniel Stenberg and Ray Satiro

Bug: https://curl.haxx.se/docs/adv_20160530.html

Ref: Windows DLL hijacking with curl, CVE-2016-4802

Bug: https://github.com/curl/curl/issues/826
Reported-by: Michael Wallner

The statvfs functionality was added to libssh2 in that version, so we
switch off that functionality when built with older libraries.

Fixes #831

Regression from the previous *printf() rearrangements, this file missed to
include the correct header to make sure snprintf() works universally.

Reported-by: Moti Avrahami
Bug: https://curl.haxx.se/mail/lib-2016-05/0196.html

Added support for checking the tchar, unicode and mbcs variants of
strcat() and strncat() in the banned function list.

Now giving credit properly to github user names, fixed some UTF-8 issues
and added names discovered when contrithanks was improved.

from 1577bfa3

Prior to this change if a GitHub contributor's real name was unknown
they would be omitted from the list.

Bug: https://github.com/curl/curl/issues/824

- Free compression methods if OpenSSL 1.0.2 to avoid a memory leak.

Bug: https://github.com/curl/curl/issues/817


Reported-by:  <jveazey@users.noreply.github.com>

While compiling lib/curl_multibyte.c with '-DUSE_WIN32_IDN' etc. I was
getting:

f:\mingw32\src\inet\curl\lib\memdebug.h(38): error C2054: expected '('
to follow 'CURL_EXTERN'

f:\mingw32\src\inet\curl\lib\memdebug.h(38): error C2085:
'curl_domalloc': not in formal parameter list

Closes #818

Closes #821

The connect-to list isn't copied so as long as the handle may be used
for a transfer the list must be valid.

Bug: https://github.com/curl/curl/pull/819
Reported-by: Michael Kaufmann

See OpenSSL commit 21e001747d4a

... when generating them, not "2.0" as the protocol is called just
HTTP/2 and nothing else.

Closes https://github.com/curl/curl/pull/816

The preprocessor check that sets up the 32bit defines for non-configure
builds didn't work properly for MIPS systems as __mips__ is defined for
both 32bit and 64bit. Now __LP64__ is also checked and indicates 64bit.

Reported-by: Tomas Jakobsson
Fixes #813

For the Windows XP toolset of Visual C++ 2013/2015, the old Windows SDK
7.1 is used. In this case, _USING_V110_SDK71_ is defined.

Closes #812

Reported-by: Paul Howarth
Bug: https://curl.haxx.se/mail/lib-2016-05/0116.html

Reported-by: Ray Satiro
Bug: https://curl.haxx.se/mail/lib-2016-05/0113.html