Revert changes relative to lib/*.[ch] recent renaming

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

1 files changed, 0 insertions, 75 deletions

diff --git a/lib/curl_hostsyn.c b/lib/curl_hostsyn.c
deleted file mode 100644
index 9a26f8d44..000000000
--- a/lib/curl_hostsyn.c
+++ /dev/null
@@ -1,75 +0,0 @@
-/***************************************************************************
- *                                  _   _ ____  _
- *  Project                     ___| | | |  _ \| |
- *                             / __| | | | |_) | |
- *                            | (__| |_| |  _ <| |___
- *                             \___|\___/|_| \_\_____|
- *
- * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al.
- *
- * This software is licensed as described in the file COPYING, which
- * you should have received as part of this distribution. The terms
- * are also available at http://curl.haxx.se/docs/copyright.html.
- *
- * You may opt to use, copy, modify, merge, publish, distribute and/or sell
- * copies of the Software, and permit persons to whom the Software is
- * furnished to do so, under the terms of the COPYING file.
- *
- * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
- * KIND, either express or implied.
- *
- ***************************************************************************/
-
-#include "curl_setup.h"
-
-#ifdef HAVE_NETINET_IN_H
-#include <netinet/in.h>
-#endif
-#ifdef HAVE_NETDB_H
-#include <netdb.h>
-#endif
-#ifdef HAVE_ARPA_INET_H
-#include <arpa/inet.h>
-#endif
-#ifdef __VMS
-#include <in.h>
-#include <inet.h>
-#endif
-
-#ifdef HAVE_PROCESS_H
-#include <process.h>
-#endif
-
-#include "curl_urldata.h"
-#include "curl_sendf.h"
-#include "curl_hostip.h"
-#include "curl_hash.h"
-#include "curl_share.h"
-#include "curl_strerror.h"
-#include "curl_url.h"
-
-#define _MPRINTF_REPLACE /* use our functions only */
-#include <curl/mprintf.h>
-
-#include "curl_memory.h"
-/* The last #include file should be: */
-#include "curl_memdebug.h"
-
-/***********************************************************************
- * Only for builds using synchronous name resolves
- **********************************************************************/
-#ifdef CURLRES_SYNCH
-
-/*
- * Function provided by the resolver backend to set DNS servers to use.
- */
-CURLcode Curl_set_dns_servers(struct SessionHandle *data,
-                              char *servers)
-{
-  (void)data;
-  (void)servers;
-  return CURLE_NOT_BUILT_IN;
-
-}
-
-#endif /* truly sync */