Add kotlinp, a tool to print Kotlin metadata in class/module files

At the moment, it's not published anywhere, but that may change soon

 #KT-23198

libraries/tools/kotlinp/testData/LocalClass.kt

@@ -0,0 +1,9 @@
+class A {
+    init {
+        class L<T> {
+            inner class I
+
+            fun x(l: L<I>) {}
+        }
+    }
+}