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

libraries/tools/runtime/pom.xml

@@ -34,6 +34,7 @@
                                 <copy todir="${basedir}/target/copied-sources">
                                     <fileset dir="${basedir}/../../../core/builtins/src"/>
                                     <fileset dir="${basedir}/../../../core/runtime.jvm/src"/>
+                                    <fileset dir="${basedir}/../../../core/reflection/src"/>
                                 </copy>
                             </target>
                         </configuration>