Do not return nested/local classes as a part of package fragment

#KT-13757 Fixed

compiler/testData/compileKotlinAgainstCustomBinaries/prohibitNestedClassesByDollarName/main.kt

@@ -0,0 +1,10 @@
+import test.Outer
+import test.JavaOuter
+
+fun main(args: Array<String>) {
+    Outer.Nested()
+    test.`Outer$Nested`()
+
+    JavaOuter.JavaNested()
+    test.`JavaOuter$JavaNested`()
+}