Kapt: Add runtime library, move all modules inside the 'kapt3' directory

plugins/kapt3/kapt3-compiler/testData/kotlinRunner/NestedClasses.kt

@@ -0,0 +1,15 @@
+package test
+
+internal class Simple {
+    @MyAnnotation
+    fun myMethod() {}
+
+    class NestedClass {
+        class NestedNestedClass
+    }
+
+    inner class InnerClass
+    companion object
+}
+
+internal annotation class MyAnnotation