- added a helper class "meth" that helps with choosing overloads that differ in argument count/types.

- use meth<Args...>::use_const( &Class::Func ) for the const version with given Arguments
- use meth<Args...>::use_nonconst( &Class::Func ) for the non-const version with given Arguments
- use meth<Args...>::use_auto( &Class::Func ) if there is only a const or non-const version with given Arguments
- Note: As of VC++2013RC IntelliSense will squiggle client code using these methods, however it compiles fine.