Add a C++ client for presents.

It provides code generators for streamables, services and receivers, but not DObject.  It uses
Apple's CFNetwork for its sockets and builds with XCode, so it's limited to OS X and iOS. It should
be straightforward to replace both to make it cross-platform.



git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@6264 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/cpp/presents/SocketStream.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "DisconnectReason.h"
+#include "io/InputStream.h"
+#include "io/OutputStream.h"
+
+namespace presents {
+class SocketStream : public InputStream, public OutputStream
+{
+public:
+    virtual ~SocketStream() {};
+    virtual void close () = 0;
+    virtual void update (float dt) = 0;
+    virtual connection_t onDisconnect (const DisconnectEvent::slot_type& slot) = 0;
+};
+
+SocketStream* createSocketStream (const char* hostname, int port);
+}