REPL overload resolution ambiguity

Fix overload resolution ambiguity in REPL. Note, resolution for
functions declared in script is very different from regular programs:
in scripts function declared later wins. See
functionOverloadResolutionAnyBeatsString for example.

#KT-2272 Fixed

compiler/testData/repl/functionOverloadResolutionAnyBeatsString.repl

@@ -0,0 +1,6 @@
+>>> fun foo(s: String) = "string"
+null
+>>> fun foo(a: Any) = "any"
+null
+>>> foo("a")
+any