-modified the default FdPollGrp implementation on windows if the Stack is not provided with an external FdPollGrp
   // If PollGrp is not passed in, then EventStackThead isn't being used and the application
   // is most likely implementing a select/process loop to drive the stack - in this case
   // we want windows to default to the fdset implementation, since the Poll implementation on
   // windows does not support the select/process loop
-removed rend from building in VS configurations, since it requires boost