Enable command execution, force destruction

src/de/steamwar/bungeecore/Subserver.java

@@ -130,11 +130,15 @@ public class Subserver implements Runnable {
         }
     }
 
+    public void execute(String command) {
+        writer.println(command);
+    }
+
     public void stop(){
-        writer.println("stop");
+        execute("stop");
         try {
             if(!process.waitFor(1, TimeUnit.MINUTES))
-                process.destroy();
+                process.destroyForcibly();
             thread.join();
         }catch(InterruptedException e){
             logger.log(Level.SEVERE, "Subserver stop interrupted!", e);