Provide "toString" for reflection objects

compiler/testData/codegen/boxWithStdlib/reflection/methodsFromAny/classToString.kt

@@ -0,0 +1,14 @@
+import kotlin.test.*
+import kotlin.reflect.jvm.kotlin
+
+class A
+
+fun box(): String {
+    val p = javaClass<A>().kotlin
+    if ("$p" != "class A") return "Fail: $p"
+
+    val s = javaClass<String>().kotlin
+    if ("$s" != "class java.lang.String") return "Fail: $s"
+
+    return "OK"
+}