Created the SimpleUsageErrorHandler to handle the error with a simple error message

src/main/java/de/gnmyt/autoresponder/commands/usage/handler/SimpleUsageErrorHandler.java

@@ -0,0 +1,16 @@
+package de.gnmyt.autoresponder.commands.usage.handler;
+
+import de.gnmyt.autoresponder.commands.usage.UsageException;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+public class SimpleUsageErrorHandler extends UsageHandler {
+
+    @Override
+    public List<String> handleUsageException(UsageException exception) {
+        return new ArrayList<>(Collections.singletonList(exception.getMessage()));
+    }
+
+}