pop3.c: Fixed drop of final CRLF in EOB checking

Curl_pop3_write() would drop the final CRLF of a message as it was
considered part of the EOB as opposed to part of the message. Whilst
the EOB sequence needs to be searched for by the function only the
final 3 characters should be removed as per RFC-1939 section 3.

Reported by: Rich Gray
Bug: http://curl.haxx.se/mail/lib-2012-02/0051.html
pop3 test server: send terminating ".CRLF" only

With commit 035ef06bda7 applied, the test pop3 server needs to send
".\r\n" as the body terminating sequence and there needs to be a final
CRLF in the actual body in the test data file.
CURLOPT_MAIL_AUTH: added in 7.25.0

Brought in commit 0cf0ab6f300
smtp.c: Fixed an issue with writing postdata

Fixed a problem in smtp_done() when writing out the postdata as
Curl_write() would periodically return zero bytes written.
Generate lists and use symbols in --libcurl code output.

This patch improves the output of curl's --libcurl option by
generating code which builds curl_httppost and curl_slist lists, and
uses symbolic names for enum and flag values.  Variants of the
my_setopt macro in tool_setopt.h are added in order to pass extra type
information to the code-generation step in tool_setopt.c.

If curl is configured with --disable-libcurl-option then the macros
call curl_easy_setopt directly.
Add tests for curl's --libcurl output.

These tests check the output of the --libcurl option of curl,
including the improved option handling added in a related patch.
Add helper script convsrctest.pl to manipulate --libcurl tests.

The intention is to take the output of curl's --libcurl option,
as exercised in test 14xx, and generate a corresponding test15xx
in which the generated code is compiled and run.  This will verify
that the generated code behaves equivalently to the original
invocation of the curl command.

The script is not yet integrated into the configure / makefile
machinery.
test: --libcurl fixes

The line endings broke when I saved the three recent patches (my fault,
not Colin's) to 'git am' them.

Adjusted the stripping of the test program for comparing to also exclude
the SSH key file name as that will differ and use a local path name.
curl.1: updated --libcurl

With Colin Hogben's recent work, --libcurl now also works with -F and
more. Remove the previous caveat.
SMTP: Added support for returning SMTP response codes

Set the conn->data->info.httpcode variable in smtp_statemach_act() to
allow Curl_getinfo() to return the SMTP response code via the
CURLINFO_RESPONSE_CODE action.
CONNECT: fix ipv6 address in the Request-Line

Commit 466150bc64d fixed the Host: header with CONNECT, but I then
forgot the preceeding request-line. Now this too uses [brackets]
properly if a ipv6 numerical address was given.

Bug: http://curl.haxx.se/bug/view.cgi?id=3493129
Reported by: "Blacat"
libcurl docs: version corrections

Correct some inconsistencies in which version some things were added.

Bug: http://curl.haxx.se/bug/view.cgi?id=3494091
Reported by: "curlybugs"
CONTRIB: Please don't send pull requests
curl-config: only provide libraries with --libs

In line with the manpage, curl-config --libs should only provide the necessary
library flags for the linker in order to compile software with libcurl. Also
with this change, we match what the pkg-config file provides.
LWIP: don't consider HAVE_ERRNO_H to be winsock

The check for Winsock definition was a bit too broad

Bug: http://curl.haxx.se/mail/lib-2012-03/0046.html
ssh_connect: tunnel through HTTP proxy if requested
CONNECT: made generically not per-protocol

Curl_protocol_connect() now does the tunneling through the HTTP proxy if
requested instead of letting each protocol specific connection function
do it.
includes: remove inclusion of unused file http_proxy.h
access the CA source file using HTTPS
mk-ca-bundle.pl: use LWP::UserAgent with proper https verify behavior.

An alternative would be:

1. specify HTTPS_CA_DIR and/or HTTPS_CA_FILE
2. ensure that Net::SSL is being used, and IO::Socket::SSL is NOT being
   used

This question and answer explain:
http://stackoverflow.com/questions/74358/