unused parameter 's' warning in iserializer.hpp

[Jim McKim <james.h.mckim@…>]

When compiled with clang, -Wall -Wextra, the header iserializer.hpp generates an "unused parameter 's'" warning.

*** iserializer.hpp.orig	2016-02-26 08:18:34.000000000 -0500
--- iserializer.hpp	2016-02-26 08:19:09.000000000 -0500
***************
*** 232,238 ****
              }
  
              template<void D(void *)>
!             static void deleter(void * t, std::size_t s){
                  D(t);
              }
              static void invoke_delete(T * t) {
--- 232,238 ----
              }
  
              template<void D(void *)>
!             static void deleter(void * t, std::size_t){
                  D(t);
              }
              static void invoke_delete(T * t) {