j2k: flatten test cases and testData directory structure

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

j2k/testData/fileOrElement/issues/comments.kt

@@ -0,0 +1,66 @@
+// This is an end-of-line comment
+
+/*
+This is a block comment
+*/
+
+
+/*doc comment of class*/
+//one line comment of class
+//another one
+/*another doc*/
+class C {
+    // This is a class comment
+
+    /**
+     * This is a field doc comment.
+     */
+    private val i: Int = 0
+
+    /**
+     * This is a function doc comment.
+     */
+    public fun foo() {
+        /* This is a function comment */
+    }
+
+    //simple one line comment for function
+    fun f1() {
+    }
+
+    //simple one line comment for field
+    var j: Int = 0
+
+    //double c style
+    //comment before function
+    fun f2() {
+    }
+
+    //double c style
+    //comment before field
+    var k: Int = 0
+
+    //combination
+    /** of
+     */
+    //
+    /**
+     * different
+     */
+    //comments
+    fun f3() {
+    }
+
+    //combination
+    /** of
+     */
+    //
+    /**
+     * different
+     */
+    //comments
+    var l: Int = 0
+
+    /*two*/ /*comments*//*line*/
+    var z: Int = 0
+}