function get100kSetForZone(i) {
    var setParm = i % NUM_100K_SETS;
    if (setParm === 0) {
      setParm = NUM_100K_SETS;
    }

    return setParm;
  }
Given a UTM zone number, figure out the MGRS 100K set it is in.

@private
@param {number} i An UTM zone number.
@return {number} the 100k set the UTM zone is in.