Win wsa select event (#342)

* 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.

ixwebsocket/IXSelectInterruptFactory.cpp

@@ -7,20 +7,20 @@
 #include "IXSelectInterruptFactory.h"
 
 #include "IXUniquePtr.h"
-#if defined(__linux__) || defined(__APPLE__)
-#include "IXSelectInterruptPipe.h"
+#if _WIN32
+#include "IXSelectInterruptEvent.h"
 #else
-#include "IXSelectInterrupt.h"
+#include "IXSelectInterruptPipe.h"
 #endif
 
 namespace ix
 {
     SelectInterruptPtr createSelectInterrupt()
     {
-#if defined(__linux__) || defined(__APPLE__)
-        return ix::make_unique<SelectInterruptPipe>();
+#ifdef _WIN32
+        return ix::make_unique<SelectInterruptEvent>();
 #else
-        return ix::make_unique<SelectInterrupt>();
+        return ix::make_unique<SelectInterruptPipe>();
 #endif
     }
 } // namespace ix