code: function(start, end, options) {
      var values = [], i;
      for (i = start; i < end; i++) {
        if (options && options.skip) {
          if (i % options.skip === 0) {
            values.push(i);
          } else {
            values.push(undefined);
          }
        } else {
          values.push(i);
        }
      }
      return values;
    }
docs: Handy method to produce an array of numbers.
  
  @param {Integer} start A number to start at
  @param {Integer} end A number to end at
  @returns {Array} An array of values