This reverts commit 7a6d8b1b.

URL: http://curl.haxx.se/mail/lib-2013-01/0103.html

I ran the 2.59 version of autoupdate that updates obsoleted configure.ac
constructs to the 2.59 standard. With a little hands-on fiddling I
prevented it from ruining the quoting in AS_HELP_STRING() uses.

I subsequently also bumped the required autoconf version to 2.59
(released in December 2003) as I don't have an older autoconf version
around to test with and I can't be bothered to install one either...

Inspired by: Björn Stenberg
Related blog post: http://cazfi.livejournal.com/195108.html

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

  f871de00... build: make use of 76 lib/*.h renamed files
  ffd8e127... 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:

  c087374c... 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:

  13606bbf... build: make use of 93 lib/*.c renamed files
  5b6e7927... build: rename 93 lib/*.c files
  7d83dfff... build: commit 13606bbf 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

93 *.c source files renamed to use our standard naming scheme.

This change affects 77 files in libcurl's source tree.

This bumps the minimal supported version of NSS to 3.12.x.

Configuration files such as curl_config.h and all config-*.h no longer exist
nor are generated/copied into 'src' directory, now these only exist in 'lib'
directory from where curl tool sources uses them.

Additionally old src/setup.h has been refactored into src/tool_setup.h which
now pulls lib/setup.h

The possibility of a makefile needing an include path adjustment exists.

Modify configure.ac to test for new CyaSSL Init function and remove
default install path to system.  Change to CyaSSL OpenSSL header and
proper Init in code as well.

Note that this no longer detects or works with CyaSSL before v2

The INTERNALS document suggested that compatibility should be
maintained with perl version 4, but this was untrue - scripts such as
chksource.pl and runtests.pl use perl5-isms.

Clarified the release procedure

curl_easy_duphandle() was not properly duping the ares channel. The
ares_dup() function was introduced in c-ares 1.6.0 so by starting to use
this function we also raise the bar and require c-ares >= 1.6.0
(released Dec 9, 2008) for such builds.

Reported by: Ning Dong
Bug: http://curl.haxx.se/mail/lib-2010-08/0318.html

It's not quite fair to list TFTP is a "crappy" member of the
libcurl family so I removed its mentioning.

removed trailing whitespace

renamed generated config.h to curl_config.h in order to avoid clashes when libcurl is used with other projects which also have a config.h.

in regard to C standard, third party libraries and operating systems etc.

internally