added @UnusedTestElement annotation

This is to indicate suspicious unused stuff, that we should
check and resolve. Didn't want to use TODO as we have tons of those.

tools/test-ng/src/main/java/com/evolveum/midpoint/tools/testng/UnusedTestElement.java

@@ -0,0 +1,22 @@
+package com.evolveum.midpoint.tools.testng;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Indicates unintentionally unused test, test method or any other test supporting method.
+ * For test classes it mostly means they are not in suite.
+ * Use comments, not this annotation to indicate that method/field is  prepared for future.
+ * Marking something with this annotation means a problem that should be eventually resolved.
+ */
+@Retention(RetentionPolicy.SOURCE)
+@Target({ ElementType.TYPE, ElementType.METHOD, ElementType.FIELD })
+public @interface UnusedTestElement {
+
+    /**
+     * Typically documents the reason.
+     */
+    String value() default "";
+}