Compilation fix

Author: agudys

adaa.analytics.rules/src/main/java/adaa/analytics/rules/logic/representation/IContrastExampleSet.java

@@ -0,0 +1,9 @@
+package adaa.analytics.rules.logic.representation;
+
+import com.rapidminer.example.Attribute;
+import com.rapidminer.example.ExampleSet;
+
+public interface IContrastExampleSet extends ExampleSet {
+
+    public Attribute getContrastAttribute();
+}