libcurl inappropriate GSSAPI delegation. Full details at
http://curl.haxx.se/docs/adv_20110623.html

This is a security flaw. See curl advisory 20110623 for details.

Reported by: Richard Silverman

[pop3] remove extra space in LIST command

Some servers, e.g. mail.bezeqint.net:110, consider it a syntax error

compiler warning: conditional expression is constant

compiler warning: variable is initialized but not referenced

adding unit test for Curl_llist_move, documenting unit-tested functions
in llist.c, changing unit-test to unittest, replacing assert calls with
abort_unless calls

The CURLFORM_STREAM is documented to only insert a file name (and thus
look like a file upload) in the part if CURLFORM_FILENAME is set, but in
reality it always inserted a filename="" and if CURLFORM_FILENAME wasn't
set, it would insert insert rubbish (or possibly crash).

This is now fixed to work as documented, and test 554 has been extended
to verify this.

Reported by: Sascha Swiercy
Bug: http://curl.haxx.se/mail/lib-2011-06/0070.html

Properly deal with the fact that the last fread() call most probably is
a short read, and when using callbacks in fact all calls can be short
reads. No longer consider a file read done until it returns a 0 from the
read function.

Reported by: Aaron Orenstein
Bug: http://curl.haxx.se/mail/lib-2011-06/0048.html

If a piece is set to use a callback to get the data, it should not be
treated as data. It unfortunately also requires that curl_easy_perform()
or similar has been used as otherwise the callback function hasn't been
figured out and curl_formget won't know how to get the content.

Due to a design flaw, the CURLFORM_STREAM option doesn't really work
with curl_formget until after curl_easy_perform (or similar).

We don't author the bindings, they are created outside the main project.

These were just warnings in test code but it still makes it nicer to not
generate them.

Typecast when converting to int from long to avoid some compiler warnings

Removing dynamic allocations also simplifies the test.

The test code that was #ifdef'ed in the code was converted into unit
tests in test case 1309. I also removed the #if 0'ed code from splay.c

With "@unittest: [num]" in the header comment for each tested function.
Shows we have a log way to go still...

This is a few first rather basic tests of curl_formadd() and
curl_formget(). Should serve as building blocks to add more variations
to the test.