* Fix#323: Missing SelectInterrupt implementation for Windows
Using WSAEventSelect, WSAWaitForMultipleEvents and WSAEnumNetworkEvents to emulate poll() with an interrupt-event.
* Cleanup
* Fixed incomplete comment.
* Switched ifdefs to support other Unixes with pipe file descriptors
* Fixed: SelectInterrupt fallback code for getFd()==-1 && getEvent()==nullptr converted a PollResultType::Timeout into a ReadyForRead causing the HttpClient to fail because it uses a hard-coded "SelectInterrupt" instance that doesn't implement getFd() and getEvent().
* Fixed gcc compile errors
* - HttpClient now uses the SelectInterruptFactory
- Fixed wrong ix::poll result when using Windows WSA functions
* We must deselect the networkevents from the socket event. Otherwise the socket will report states that aren't there.