j2k: flatten test cases and testData directory structure

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

j2k/testData/fileOrElement/constructors/parameterDefaults2.kt

@@ -0,0 +1,12 @@
+package pack
+
+
+fun C(a1: Int, b1: Int, c1: Int): C {
+    return C(a1, b1, c1, 0, 0)
+}
+
+fun C(b: Byte): C {
+    return C(b.toInt(), 0, 0, 0, 0)
+}
+
+class C(a: Int = 0, b: Int = 0, c: Int = 0, d: Int = 0, e: Int = 0)