Initial check in of support for upcasting during function invocation. No examples or tests are checked in yet. Some reorg was necessary to get things compiling in the right order. Is not currently thread safe and probably does not work properly across module boundaries

include/chaiscript/dispatchkit/proxy_functions.hpp

@@ -20,6 +20,8 @@
 
 namespace chaiscript
 {
+  class Boxed_POD_Value;
+
   /**
    * Helper for building a list of parameters for calling a Proxy_Function
    * it does automatic conversion to Boxed_Value types via operator<<
@@ -97,7 +99,8 @@ namespace chaiscript
             if (ti.is_undef() || vals[0].get_type_info().is_undef()
                 || ti.bare_equal(user_type<Boxed_Value>())
                 || ti.bare_equal(user_type<Boxed_POD_Value>())
-                || ti.bare_equal(vals[0].get_type_info()))
+                || ti.bare_equal(vals[0].get_type_info())
+                || dynamic_cast_converts(ti, vals[0].get_type_info()) )
             {
               return true;
             } else {