j2k: flatten test cases and testData directory structure

Move j2k/test/tests -> j2k/tests, j2k/test/testData -> j2k/testData

j2k/testData/fileOrElement/toKotlinClasses/iterableAndIterator3.java

@@ -0,0 +1,16 @@
+//file
+package demo;
+
+import java.util.Iterator;
+
+class Test implements Iterable<String> {
+    @Override
+    public Iterator<String> iterator() {
+        return null;
+    }
+
+    public Iterator<String> push(Iterator<String> i) {
+        Iterator<String> j = i;
+        return j;
+    }
+}