Previously it would access a NULL pointer and die.

Bug: http://curl.haxx.se/mail/lib-2011-06/0170.html
Reported by: Christian Hagele

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

Reported by: Richard Silverman

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.

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

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...

When closing a connection, the speedchecker's timestamp is now deleted
so that it cannot accidentally be used by a fresh connection on the same
handle when examining the transfer speed.

Bug: https://bugzilla.redhat.com/679709

When a time condition isn't met, so that no body is delivered to the
application even though a 2xx response is being read from the server, we
must close the connection to avoid a re-use of the connection to be
completely tricked.

Added test 1128 to verify.

Typecasts added since I changed more code to use long for timeouts

It was mostly typecasted to int all over the code so switching to long
instead all over should be a net gain.

I removed the prefix as well accordingly.

Fix compiler warning: cast increases required alignment

Source files given with relative paths do not have the
-D directory specifier prepended.

Fix compiler warning: conversion may lose significant bits

When switching to HTTP because a HTTP proxy is being used, the existing
handler is now checked if it already is "compatible". This allows the https
handler remain while other non-http handlers will be redirected.

Bug: http://curl.haxx.se/mail/lib-2011-05/0214.html
Reported by: Jerome Robert

Fix compiler warning: variable was set but never used

Fix compiler warning: clobber ignored