Change reader null message

Signed-off-by: Lixfel <agga-games@gmx.de>

src/de/steamwar/bungeecore/Node.java

@@ -211,6 +211,8 @@ public abstract class Node {
                 if(!process.waitFor(1, TimeUnit.SECONDS))
                     throw new IOException(hostname + " timeout");
                 try (BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()))) {
+                    if(reader == null)
+                        throw new IOException("Why reader null? " + process.getInputStream());
                     calcLoadLimit(reader, reader);
                 }
             } catch (IOException e) {