offer alternate instanciation also for new compilers; refs #6

src/mrw/args.hxx

@@ -175,11 +175,9 @@ namespace mrw {
     }
     struct decl {
         typedef std::vector<param_ptr> param_list;
-#ifdef MRW__OLD_PRE11_COMPILER
         decl(std::string p1, std::string p2, std::string p3, param_list p4):
             short_arg(p1), long_arg(p2), desc(p3), params(p4) {
         }
-#endif
         std::string short_arg;
         std::string long_arg;
         std::string desc;