Get rid of all classes except kotlin.reflect.KFunction, which will be used to
represent all kinds of simple functions.
Lots of changes to test data are related to the fact that KFunction is not an
extension function (as opposed to KMemberFunction and KExtensionFunction who
were) and so a member or an extension function reference now requires all
arguments be passed to it in the parentheses, including receivers. This is
probably temporary until we support calling any function both as a free
function and as an extension. In JS, functions and extension functions are not
interchangeable, so tests on this behavior are removed until this is supported
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
