Fix stop joining thread before interrupting Selector.select

FixesTooTallNate#259

Author: bendem

src/main/java/org/java_websocket/server/WebSocketServer.java

@@ -216,16 +216,10 @@ public void stop( int timeout ) throws InterruptedException{
  }
 
 synchronized ( this ){
-if( selectorthread != null ){
-if( Thread.currentThread() != selectorthread ){
-
- }
-if( selectorthread != Thread.currentThread() ){
-if( socketsToClose.size() > 0 )
-selectorthread.join( timeout );// isclosed will tell the selectorthread to go down after the last connection was closed
-selectorthread.interrupt();// in case the selectorthread did not terminate in time we send the interrupt
-selectorthread.join();
- }
+if( selectorthread != null && selectorthread != Thread.currentThread() ){
+selector.wakeup();
+selectorthread.interrupt();
+selectorthread.join( timeout );
  }
  }
  }