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, 66 insertions, 0 deletions

diff --git a/lib/splay.h b/lib/splay.h
new file mode 100644
index 000000000..49a6dec41
--- /dev/null
+++ b/lib/splay.h
@@ -0,0 +1,66 @@
+#ifndef HEADER_CURL_SPLAY_H
+#define HEADER_CURL_SPLAY_H
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1997 - 2011, 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 "setup.h"
+
+struct Curl_tree {
+  struct Curl_tree *smaller; /* smaller node */
+  struct Curl_tree *larger;  /* larger node */
+  struct Curl_tree *same;    /* points to a node with identical key */
+  struct timeval key;        /* this node's "sort" key */
+  void *payload;             /* data the splay code doesn't care about */
+};
+
+struct Curl_tree *Curl_splay(struct timeval i,
+                             struct Curl_tree *t);
+
+struct Curl_tree *Curl_splayinsert(struct timeval key,
+                                   struct Curl_tree *t,
+                                   struct Curl_tree *newnode);
+
+#if 0
+struct Curl_tree *Curl_splayremove(struct timeval key,
+                                   struct Curl_tree *t,
+                                   struct Curl_tree **removed);
+#endif
+
+struct Curl_tree *Curl_splaygetbest(struct timeval key,
+                                    struct Curl_tree *t,
+                                    struct Curl_tree **removed);
+
+int Curl_splayremovebyaddr(struct Curl_tree *t,
+                           struct Curl_tree *removenode,
+                           struct Curl_tree **newroot);
+
+#define Curl_splaycomparekeys(i,j) ( ((i.tv_sec)  < (j.tv_sec))  ? -1 : \
+                                   ( ((i.tv_sec)  > (j.tv_sec))  ?  1 : \
+                                   ( ((i.tv_usec) < (j.tv_usec)) ? -1 : \
+                                   ( ((i.tv_usec) > (j.tv_usec)) ?  1 : 0 ))))
+
+#ifdef DEBUGBUILD
+void Curl_splayprint(struct Curl_tree * t, int d, char output);
+#else
+#define Curl_splayprint(x,y,z) Curl_nop_stmt
+#endif
+
+#endif /* HEADER_CURL_SPLAY_H */