Follow-up to 1c4fa67e8a8fcf6

STRERROR_LEN is the constant used throughout the library to set the size
of the buffer on the stack that the curl strerror functions write to.

Prior to this change some extended length Windows error messages could
be truncated.

Closes https://github.com/curl/curl/pull/4920

- In all code call Curl_winapi_strerror instead of Curl_strerror when
  the error code is known to be from Windows GetLastError.

Curl_strerror prefers CRT error codes (errno) over Windows API error
codes (GetLastError) when the two overlap. When we know the error code
is from GetLastError it is more accurate to prefer the Windows API error
messages.

Reported-by: Richard Alcock

Fixes https://github.com/curl/curl/issues/4550
Closes https://github.com/curl/curl/pull/4581

Instead of using a fixed 256 byte buffer in the connectdata struct.

In my build, this reduces the size of the connectdata struct by 11.8%,
from 2160 to 1904 bytes with no functionality or performance loss.

This also fixes a bug in schannel's Curl_verify_certificate where it
called Curl_sspi_strerror when it should have called Curl_strerror for
string from GetLastError. the only effect would have been no text or the
wrong text being shown for the error.

Co-authored-by: Jay Satiro

Closes #3612

CVE-2016-8625

Bug: https://curl.haxx.se/docs/adv_20161102K.html
Reported-by: Christian Heimes

This reverts renaming and usage of lib/*.h header files done
28-12-2012, reverting 2 commits:

  f871de0... build: make use of 76 lib/*.h renamed files
  ffd8e12... build: rename 76 lib/*.h files

This also reverts removal of redundant include guard (redundant thanks
to changes in above commits) done 2-12-2013, reverting 1 commit:

  c087374... curl_setup.h: remove redundant include guard

This also reverts renaming and usage of lib/*.c source files done
3-12-2013, reverting 3 commits:

  13606bb... build: make use of 93 lib/*.c renamed files
  5b6e792... build: rename 93 lib/*.c files
  7d83dff... build: commit 13606bbfde follow-up 1

Start of related discussion thread:

  http://curl.haxx.se/mail/lib-2013-01/0012.html

Asking for confirmation on pushing this revertion commit:

  http://curl.haxx.se/mail/lib-2013-01/0048.html

Confirmation summary:

  http://curl.haxx.se/mail/lib-2013-01/0079.html

NOTICE: The list of 2 files that have been modified by other
intermixed commits, while renamed, and also by at least one
of the 6 commits this one reverts follows below. These 2 files
will exhibit a hole in history unless git's '--follow' option
is used when viewing logs.

  lib/curl_imap.h
  lib/curl_smtp.h

76 private header files renamed to use our standard naming scheme.

This commit only does the file renaming.

----------------------------------------

  renamed:    amigaos.h -> curl_amigaos.h
  renamed:    arpa_telnet.h -> curl_arpa_telnet.h
  renamed:    asyn.h -> curl_asyn.h
  renamed:    axtls.h -> curl_axtls.h
  renamed:    bundles.h -> curl_bundles.h
  renamed:    conncache.h -> curl_conncache.h
  renamed:    connect.h -> curl_connect.h
  renamed:    content_encoding.h -> curl_content_encoding.h
  renamed:    cookie.h -> curl_cookie.h
  renamed:    cyassl.h -> curl_cyassl.h
  renamed:    dict.h -> curl_dict.h
  renamed:    easyif.h -> curl_easyif.h
  renamed:    escape.h -> curl_escape.h
  renamed:    file.h -> curl_file.h
  renamed:    fileinfo.h -> curl_fileinfo.h
  renamed:    formdata.h -> curl_formdata.h
  renamed:    ftp.h -> curl_ftp.h
  renamed:    ftplistparser.h -> curl_ftplistparser.h
  renamed:    getinfo.h -> curl_getinfo.h
  renamed:    gopher.h -> curl_gopher.h
  renamed:    gtls.h -> curl_gtls.h
  renamed:    hash.h -> curl_hash.h
  renamed:    hostcheck.h -> curl_hostcheck.h
  renamed:    hostip.h -> curl_hostip.h
  renamed:    http.h -> curl_http.h
  renamed:    http_chunks.h -> curl_http_chunks.h
  renamed:    http_digest.h -> curl_http_digest.h
  renamed:    http_negotiate.h -> curl_http_negotiate.h
  renamed:    http_proxy.h -> curl_http_proxy.h
  renamed:    if2ip.h -> curl_if2ip.h
  renamed:    imap.h -> curl_imap.h
  renamed:    inet_ntop.h -> curl_inet_ntop.h
  renamed:    inet_pton.h -> curl_inet_pton.h
  renamed:    krb4.h -> curl_krb4.h
  renamed:    llist.h -> curl_llist.h
  renamed:    memdebug.h -> curl_memdebug.h
  renamed:    multiif.h -> curl_multiif.h
  renamed:    netrc.h -> curl_netrc.h
  renamed:    non-ascii.h -> curl_non-ascii.h
  renamed:    nonblock.h -> curl_nonblock.h
  renamed:    nssg.h -> curl_nssg.h
  renamed:    parsedate.h -> curl_parsedate.h
  renamed:    pingpong.h -> curl_pingpong.h
  renamed:    polarssl.h -> curl_polarssl.h
  renamed:    pop3.h -> curl_pop3.h
  renamed:    progress.h -> curl_progress.h
  renamed:    qssl.h -> curl_qssl.h
  renamed:    rawstr.h -> curl_rawstr.h
  renamed:    rtsp.h -> curl_rtsp.h
  renamed:    select.h -> curl_select.h
  renamed:    sendf.h -> curl_sendf.h
  renamed:    setup.h -> curl_setup.h
  renamed:    setup_once.h -> curl_setup_once.h
  renamed:    share.h -> curl_share.h
  renamed:    slist.h -> curl_slist.h
  renamed:    smtp.h -> curl_smtp.h
  renamed:    sockaddr.h -> curl_sockaddr.h
  renamed:    socks.h -> curl_socks.h
  renamed:    speedcheck.h -> curl_speedcheck.h
  renamed:    splay.h -> curl_splay.h
  renamed:    ssh.h -> curl_ssh.h
  renamed:    sslgen.h -> curl_sslgen.h
  renamed:    ssluse.h -> curl_ssluse.h
  renamed:    strdup.h -> curl_strdup.h
  renamed:    strequal.h -> curl_strequal.h
  renamed:    strerror.h -> curl_strerror.h
  renamed:    strtok.h -> curl_strtok.h
  renamed:    strtoofft.h -> curl_strtoofft.h
  renamed:    telnet.h -> curl_telnet.h
  renamed:    tftp.h -> curl_tftp.h
  renamed:    timeval.h -> curl_timeval.h
  renamed:    transfer.h -> curl_transfer.h
  renamed:    url.h -> curl_url.h
  renamed:    urldata.h -> curl_urldata.h
  renamed:    warnless.h -> curl_warnless.h
  renamed:    wildcard.h -> curl_wildcard.h

----------------------------------------

76 private header files renamed to use our standard naming scheme.

This change affects 322 files in libcurl's source tree.