Possible upload timeout improvement.

When uploading finishes, but is not detected, the timeout should be for
"reply delay", the time that the server takes before it replies, and not
CurlTimeoutLowSpeedTime. This patch adds code that takes this failure
into account (which happened only ONCE for me on Metropolis while flying
around and using trickle (not sure if that is relevant), so it's not
that likely to improvement anything in practise. Note that it is
detected by an assertion when it happens, so that we can safely assume
it normally never happened on SL).

* Generalized PUT / POST configuration by adding
  CurlEasyRequest::setPut, which now also supports keep-alive (which
  still isn't used).
* Upload content length is now stored in CurlEasyRequest::mContentLength
* CurlEasyRequest::has_stalled() now return false if it was possbile
  that the 'upload finished' detect failed AND calls upload_finished()
  itself in that case, so it is no longer 'const'.
* If low speed is detect exactly when the last bytes are being attempted
  to be sent (unlikely scenario), then the upload gets 4 more seconds
  after which is switches to CurlTimeoutReplyDelay.
* Added EDoesAuthentication and EAllowCompressedReply to replace
  booleans, for readability and type-safety, as did EKeepAlive. Note
  that this change inverts the meaning of the compression related parameter.
* Unrelated: removed an unnecessary #include "llurlrequest.h" from
  llxmlrpcresponder.h

indra/llmessage/aicurlthread.cpp

@@ -2058,8 +2058,9 @@ size_t BufferedCurlEasyRequest::curlReadCallback(char* data, size_t size, size_t
   S32 bytes = size * nmemb;		// The maximum amount to read.
   self_w->mLastRead = self_w->getInput()->readAfter(sChannels.out(), self_w->mLastRead, (U8*)data, bytes);
   self_w->mRequestTransferedBytes += bytes;		// Accumulate data sent to the server.
+  llassert(self_w->mRequestTransferedBytes <= self_w->mContentLength);	// Content-Length should always be known, and we should never be sending more.
   // Timeout administration.
-  if (self_w->httptimeout()->data_sent(bytes))
+  if (self_w->httptimeout()->data_sent(bytes, self_w->mRequestTransferedBytes >= self_w->mContentLength))
   {
 	// Transfer timed out. Return CURL_READFUNC_ABORT which will abort with error CURLE_ABORTED_BY_CALLBACK.
 	return CURL_READFUNC_ABORT;