challenge: implement the max function

[Andrei Alexandrescu (See Website For Email)]

Andrey Khropov wrote:
> Andrei Alexandrescu (See Website for Email) wrote:
> 
>> * First off, specifying storageof(T) T as the type of a function
>> argument means that the compiler will deduce the storage class of the
>> actual argument: if the argument is an lvalue, inout will be deduced.
> 
> Ok, but now D doesn't allow to return lvalues from functions, so this won't
> satisfy (c) for any type except classes that define opMulAssign.

Future D will allow returning inout values. As you see, the maxreturn 
type might specify a storage. Sorry I forgot to mention that.

Andrei