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

lib/curl_addrinfo.c

@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2013, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * 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
@@ -20,7 +20,7 @@
  *
  ***************************************************************************/
 
-#include "curl_setup.h"
+#include "setup.h"
 
 #include <curl/curl.h>
 
@@ -45,15 +45,15 @@
 #endif
 
 #include "curl_addrinfo.h"
-#include "curl_inet_pton.h"
-#include "curl_warnless.h"
+#include "inet_pton.h"
+#include "warnless.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"
+#include "memdebug.h"
 
 
 /*
@@ -482,8 +482,8 @@ Curl_addrinfo *Curl_str2addr(char *address, int port)
  * curl_dofreeaddrinfo()
  *
  * This is strictly for memory tracing and are using the same style as the
- * family otherwise present in curl_memdebug.c. I put these ones here since
- * they require a bunch of structs I didn't want to include there.
+ * family otherwise present in memdebug.c. I put these ones here since they
+ * require a bunch of structs I didn't want to include in memdebug.c
  */
 
 void
@@ -502,8 +502,8 @@ curl_dofreeaddrinfo(struct addrinfo *freethis,
  * curl_dogetaddrinfo()
  *
  * This is strictly for memory tracing and are using the same style as the
- * family otherwise present in curl_memdebug.c. I put these ones here since
- * they require a bunch of structs I didn't want to include there.
+ * family otherwise present in memdebug.c. I put these ones here since they
+ * require a bunch of structs I didn't want to include in memdebug.c
  */
 
 int