Debug output 'typo' fix.

Don't print an extra "0x" in
  * Pipe broke: handle 0x0x2546d88, url = /

Add debug output.
Print the number of connections in the connection cache when
  adding one, and not only when one is removed.

Fix typos in comments.

... as it was before I changed the loop in commit e04ccbd5. It caused
test 2030 and 2032 to fail.

... and assign data->result only at the end. Makes the code more compact
(easier to read) and more similar to other code.

save 'result' for CURLcode types

simplifies the use of this function at little cost.

Fixes the problem when a transfer in a pipeline times out.

Even though commit 23e70e1c mentioned the v110_xp toolset, I had
forgotten to include the relevant pre-processor definitions.

warning: unused parameter 'reason'

warning: unused parameter 'easy'

Updated the usage of some legacy APIs, that are preventing curl from
compiling for Windows Store and Windows Phone build targets.

Suggested-by: Stefan Neis
Feature: http://sourceforge.net/p/curl/feature-requests/82/

Visual Studio 2012 introduced support for Windows Store apps as well as
supporting Windows Phone 8. Introduced build targets that allow more
modern APIs to be used as certain legacy ones are not available on these
new platforms.

Just like in the NTLM code, added infof() failure messages for
DIGEST-MD5 and GSSAPI authentication when base64 decoding fails.

For consistency renamed USE_KRB5 to USE_KERBEROS5.

There was a mismatch in function parameter names.

This variable is only used with HAVE_GSSAPI is defined by the FTP code
so let's place the definition with the other GSS-API based variables.

Rather than define the function as extern in the source files that use
it, moved the function declaration into the SASL header file just like
the Digest and NTLM clean-up functions.

Additionally, added a function description comment block.

Previously if HTTP/2 traffic is appended to HTTP Upgrade response header
(thus they are in the same buffer), the trailing HTTP/2 traffic is not
processed and lost.  The appended data is most likely SETTINGS frame.
If it is lost, nghttp2 library complains server does not obey the HTTP/2
protocol and issues GOAWAY frame and curl eventually drops connection.
This commit fixes this problem and now trailing data is processed.

It isn't used anywhere!

Reported-by: Carlo Wood

Fix detection of the AsynchDNS feature which not just depends on
pthreads support, but also on whether USE_POSIX_THREADS is set or not.
Caught by test 1014.

This patch adds a new ENABLE_THREADED_RESOLVER option (corresponding to
--enable-threaded-resolver of autotools) which also needs a check for
HAVE_PTHREAD_H.

For symmetry with autotools, CURL_USE_ARES is renamed to ENABLE_ARES
(--enable-ares). Checks that test for the availability actually use
USE_ARES instead as that is the result of whether a-res is available or
not (in practice this does not matter as CARES is marked as required
package, but nevertheless it is better to write the intent).

Signed-off-by: Peter Wu <peter@lekensteyn.nl>

vtls.c:185:46: warning: unused parameter 'data'

In preparation for moving the NTLM message code into the SASL module,
and separating the native code from the SSPI code, added functions that
simply call the functions in curl_ntlm_msg.c.

In preparation for moving the NTLM message code into the SASL module
use the SASL functions in the HTTP code instead.

... so that non-configure builds get the correct functions too based on
the libssh2 version used.

... if the libssh2 version is new enough.

Bug: http://curl.haxx.se/bug/view.cgi?id=1448