Have Qt poll for shutdown requested, the QT way.

src/init.cpp

@@ -61,8 +61,8 @@ enum BindFlags {
 // immediately and the parent exits from main().
 //
 // Shutdown for Qt is very similar, only it uses a QTimer to detect
-// fRequestShutdown getting set (either by RPC stop or SIGTERM)
-// and then does the normal Qt shutdown thing.
+// fRequestShutdown getting set, and then does the normal Qt
+// shutdown thing.
 //
 
 volatile bool fRequestShutdown = false;
@@ -71,6 +71,10 @@ void StartShutdown()
 {
     fRequestShutdown = true;
 }
+bool ShutdownRequested()
+{
+    return fRequestShutdown;
+}
 
 static CCoinsViewDB *pcoinsdbview;