As the GSS-API and SSPI based source files are no longer library/API
specific, following the extraction of that authentication code to the
vauth directory, combine these files rather than maintain two separate
versions.

Part 2 of 2 - Moved the GSS-API based Negotiate authentication code.

Part 1 of 2 - Moved the SSPI based Negotiate authentication code.

Not picked up by checksrc or Visual Studio but my own code review, this
would haven broken Intel based Unix builds - Perhaps I should learn to
type on my laptop's keyboard before committing!

warning C4244: '=': conversion from 'int' to 'unsigned short', possible
                    loss of data

Closes #729
Closes #728

Renamed all the SASL functions that moved to the new vauth directory to
include the correct module name.

As most of this work was performed in 2015 but not pushed until 2016
updated the copyright year to reflect the public facing changes.

Updated the makefiles and Visual Studio project files to support moving
the authentication code to the new lib/vauth directory that was started
in commit 0d04e859.

Add ALPN support for schannel. This allows cURL to negotiate
HTTP/2.0 connections when built with schannel.

Closes #724

Use the local, reasonably updated, 'now' value when creating the message
string to output for the timeout condition.

Fixes #619

... so we don't need extra boringssl precautions for for
HAVE_ERR_REMOVE_THREAD_STATE_NOARG.

Pointed-out-by: David Benjamin

The removed arg is only done in OpenSSL

Bug: https://twitter.com/xtraemeat/status/712564874098917376

... and update the coming release dates a bit

Follow up to commit a8c7f0fc prior to release.

Bug: https://github.com/curl/curl/issues/685

It seems we may have some autobuild problems after this commit went
in. Trying to see if a revert helps to get them back.

This reverts commit 2716350d.

... makes it a lot faster

... to make it look nicer in markdown outputa

- Do not use wolfSSL's sample user-setting files.

wolfSSL starting in v3.9.0 has added their own sample user settings that
are applied by default, but we don't use them because we have our own
settings.

- Do not use wolfSSL's Visual Studio Unicode character setting.

wolfSSL Visual Studio projects use the Unicode character set however our
settings and options imitate mingw build which does not use the Unicode
character set. This does not appear to have any effect at the moment but
better safe than sorry.


These changes are backwards compatible with earlier versions.

warning C4189: 'data': local variable is initialized but not referenced

...and some minor formatting/spacing changes.

Support for the (undocumented) AuthorizedKeysFile2 was removed in
OpenSSH 5.9, released in September 2011

Closes #715

warning C4189: 'data': local variable is initialized but not referenced