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.

CMakeLists.txt

@@ -41,6 +41,7 @@ set( IXWEBSOCKET_SOURCES
     ixwebsocket/IXSelectInterrupt.cpp
     ixwebsocket/IXSelectInterruptFactory.cpp
     ixwebsocket/IXSelectInterruptPipe.cpp
+    ixwebsocket/IXSelectInterruptEvent.cpp
     ixwebsocket/IXSetThreadName.cpp
     ixwebsocket/IXSocket.cpp
     ixwebsocket/IXSocketConnect.cpp
@@ -80,6 +81,7 @@ set( IXWEBSOCKET_HEADERS
     ixwebsocket/IXSelectInterrupt.h
     ixwebsocket/IXSelectInterruptFactory.h
     ixwebsocket/IXSelectInterruptPipe.h
+    ixwebsocket/IXSelectInterruptEvent.h
     ixwebsocket/IXSetThreadName.h
     ixwebsocket/IXSocket.h
     ixwebsocket/IXSocketConnect.h