code: public SmartBinder spread(String baseName, int count) {
          return new SmartBinder(this, signature().spread(baseName, count), binder.spread(count));
      }
docs: Spread a trailing array into count number of arguments, using the
  natural component type for the array. Build names for the arguments
  using the given baseName plus the argument's index.
  
  Example:
  Current binder has a signature of (int, String[])void. We want
  to spread the strings into five arguments named "str".
  
  <code>binder = binder.spread("str", 5)</code>
  
  The resulting signature will have five trailing arguments named
  "arg0" through "arg4".
  
  @param baseName the base name from which to create the new argument names
  @param count    the count of arguments to spread
  @return a new SmartBinder with the spread applied