WIP: Make curl thread code robust and flexible.

Conflicts:

	indra/llmessage/llcurl.cpp
	indra/llmessage/llcurl.h
	indra/newview/app_settings/settings.xml
	indra/newview/llappviewer.cpp
	indra/newview/llmeshrepository.cpp

Resolved:

	indra/llmessage/llcurl.cpp:

	  Basically removed (not used anyway)

	indra/llmessage/llcurl.h:

	  Basically removed (just includes aiculr.h now)

	indra/newview/app_settings/settings.xml:

	  CurlUseMultipleThreads was remvoved.
	  CurlMaximumNumberOfHandles and CurlRequestTimeOut
	  are still in there, but unused at the moment.

	indra/newview/llappviewer.cpp:

	  CurlMaximumNumberOfHandles and CurlRequestTimeOut
	  are unused at the moment.

	indra/newview/llmeshrepository.cpp:

	  Lock mSignal always (is unlocked inside wait()).
	  Use mSignal lock to see if we are waiting; remove mWaiting.
	  Return false from the MeshFetch functions iff we have to retry
	  a HTTP fetch. Catch the error exception thrown by getByteRange
	  instead of using it's return value (always returns true
	  anyway).

indra/llcommon/llqueuedthread.h

@@ -110,6 +110,8 @@ public:
 				return mPriority > second.mPriority;
 		}
 
+		virtual void deleteRequest(); // Only method to delete a request
+
 	protected:
 		status_t setStatus(status_t newstatus)
 		{
@@ -125,7 +127,6 @@ public:
 		
 		virtual bool processRequest() = 0; // Return true when request has completed
 		virtual void finishRequest(bool completed); // Always called from thread after request has completed or aborted
-		virtual void deleteRequest(); // Only method to delete a request
 
 		void setPriority(U32 pri)
 		{