moved stream into synergy namespace (to prevent naming collision in win libs)

implemented ipc "hello" message (to identify client type)
integ tests working for hello message, but use of ipc in main program has problem with events.

src/test/unittests/io/CMockStream.h

@@ -22,7 +22,7 @@
 
 class IEventQueue;
 
-class CMockStream : public IStream
+class CMockStream : public synergy::IStream
 {
 public:
 	CMockStream(IEventQueue& eventQueue) : IStream(eventQueue) { }