- removed all the possibly destructor-throwing proxies used by call_function and call_member alltogether, if you want to supply policies, there's a new template parameter to those functions (you had to specify the return type as a template parameter anyways)

- reworked the public policies to be in line syntactically
- added perfect forwarding to call_function and call_member up to the converters (and added a missing overload to default_converter that caused a bug thereby)