Add inverting of validator, removes more boilerplate

src/de/steamwar/command/AbstractSWCommand.java

@@ -354,17 +354,21 @@ public abstract class AbstractSWCommand<T> {
 
         boolean local() default false;
 
+        boolean invert() default false;
+
         class Handler<T> implements AbstractValidator<T, Object> {
 
             private AbstractValidator<T, Object> inner;
+            private boolean invert;
 
             public Handler(AbstractSWCommand.Validator validator, Class<?> clazz, Map<String, AbstractValidator<T, ?>> localValidator) {
                 inner = (AbstractValidator<T, Object>) SWCommandUtils.getValidator(validator, clazz, localValidator);
+                invert = validator.invert();
             }
 
             @Override
             public boolean validate(T sender, Object value, MessageSender messageSender) {
-                return inner.validate(sender, value, messageSender);
+                return inner.validate(sender, value, messageSender) ^ invert;
             }
         }
     }