Introduce module 'reflection', move KFunctionN to it

Metadata for KFunction classes is now longer serialized along with built-in
classes. This effectively means that it's no longer possible to find KFunction
classes via dependency on built-ins. There should be a kotlin-runtime library
in the specified classpath for reflection types to be resolvable.

A lot of tests were moved and changed, because tests on callable references
require stdlib in classpath from now on

compiler/testData/diagnostics/testsWithStdLib/callableReference/function/renameOnImport.kt

@@ -0,0 +1,27 @@
+// FILE: a.kt
+
+package other
+
+fun foo() {}
+
+class A {
+    fun bar() = 42
+}
+
+fun A.baz(<!UNUSED_PARAMETER!>x<!>: String) {}
+
+// FILE: b.kt
+
+import other.foo as foofoo
+import other.A as AA
+import other.baz as bazbaz
+
+fun main() {
+    val x = ::foofoo
+    val y = AA::bar
+    val z = AA::bazbaz
+
+    x : KFunction0<Unit>
+    y : KMemberFunction0<AA, Int>
+    z : KExtensionFunction1<AA, String, Unit>
+}