Start moving towards C++ only UI code. Assume C++ for the replay API

* The C# P/Invoke stuff doesn't directly use the header, and we are soon
  going to deprecate the C interface entirely.

qrenderdoc/Code/RemoteHost.cpp

@@ -62,7 +62,7 @@ void RemoteHost::CheckStatus()
     return;
   }
 
-  RemoteServer *rend = NULL;
+  IRemoteServer *rend = NULL;
   ReplayCreateStatus status =
       RENDERDOC_CreateRemoteServerConnection(Hostname.toUtf8().data(), 0, &rend);