All C and H files now (should) feature the proper project curl source
code header, which includes basic info, a copyright statement and some
basic disclaimers.

Also spelling fix for RECIPIENT #define.

Even if libcurl might to do it for us, it is more correct.

Without this you won't get the next (Subject) line.

This example shows how to send SMTP with TLS

Add a simple SMTP example program, patterned after some of the existing
examples, and the curl application.

This version addresses issues raised by David Woodhouse on comments in
the simplesmtp.c example.

Bug: http://curl.haxx.se/mail/lib-2010-12/0192.html

and the traditional source header

This script is the start of a helper tool that scans a source code and
outputs the most recent libcurl version it finds symbols for. Meaning
that if there's no conditions in the code, that's the earliest libcurl
version the scanned code requires.

It is not added to the Makefile.am yet as it is still a bit crude, but
I'm committing it to keep it and allow us to work on it.

I've made the code intended using curl-style now to look more like other
examples.

My previous "fix" was a bit too invasive but is now fixed again.

An example application source code sending SMTP mail with the multi
interface. It is based on the code Alona Rossen provided, which in turn
is based on existing example/test code, and I converted it even more
into a decent example with a fair multi API use, put the info required
to edit at the top and I added some comments.

all multi and hiper examples:

* don't loop curl_multi_perform calls, that was <7.20.0 style, currently
  the exported multi functions will not return CURLM_CALL_MULTI_PERFORM

all hiper examples:
* renamed check_run_count to check_multi_info
* don't  compare current running handle count with previous value, this
  was the wrong way to check for finished requests, simply call
  curl_multi_info_read
* it's also safe to call curl_multi_remove_handle inside the
  curl_multi_info_read loop.

ghiper.c:
* replaced curl_multi_socket (that function is marked as obsolete) calls
  with curl_multi_socket_action calls (as in hiperfifo.c and
  evhiperfifo.c)

ghiper.c and evhiperfifo.c:
* be smart as hiperfifo.c, don't do uncessary curl_multi_* calls in
  new_conn and main

1. Remove the comment warning that it's "not been verified to work". It
   works with no problems in my testing.

2. Remove 2 unnecessary includes.

3. Remove the myrealloc(). Initialize chunk.memory with malloc() instead
   of NULL. The comments for these two parts contradicted each other.

4. Handle out of memory from realloc() instead of continuing.

5. Print a brief status message at the end.

Make the multi-interface using examples use curl_multi_timeout to
properly educate users how to do things.

Also tweaked comments in certain examples using curl_multi_fdset().

replaced tabs with spaces

removed trailing whitespace

the code more curl-style

curl.h, adjusting auto-makefiles include path, to enhance portability to
OS's without an orthogonal directory tree structure such as OS/400.