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, 4 insertions, 5 deletions

diff --git a/src/Makefile.inc b/src/Makefile.inc
index 4e1d4271f..7ce30f0b6 100644
--- a/src/Makefile.inc
+++ b/src/Makefile.inc
@@ -9,11 +9,10 @@
 
 # libcurl has sources that provide functions named curlx_* that aren't part of
 # the official API, but we re-use the code here to avoid duplication.
-CURLX_ONES = \
-	$(top_srcdir)/lib/curl_nonblock.c \
-	$(top_srcdir)/lib/curl_rawstr.c \
-	$(top_srcdir)/lib/curl_strdup.c \
-	$(top_srcdir)/lib/curl_strtoofft.c
+CURLX_ONES = $(top_srcdir)/lib/strtoofft.c \
+	$(top_srcdir)/lib/strdup.c \
+	$(top_srcdir)/lib/rawstr.c \
+	$(top_srcdir)/lib/nonblock.c
 
 CURL_CFILES = \
 	tool_binmode.c \