cancellation refactoring

ixwebsocket/IXCancellationRequest.h

@@ -7,9 +7,13 @@
 #pragma once
 
 #include <functional>
+#include <atomic>
 
 namespace ix 
 {
     using CancellationRequest = std::function<bool()>;
+
+    CancellationRequest makeCancellationRequestWithTimeout(int seconds,
+                                                           std::atomic<bool>& requestInitCancellation);
 }