code: function roundHalfUp(num, precision) {
      var multiplier = pow(10, precision),
          numMod = parseInt((num * multiplier), 10),
          lastDigit = parseInt(num * (multiplier * 10), 10) - (numMod * 10);
      if (lastDigit < -5) {
          numMod -= 1;
      } else if (lastDigit >= 5) {
          numMod += 1;
      }
      return numMod / multiplier;
  }
docs: Rounds a number half up to the specified places.
  @example
  
  comb.number.roundHalfUp(0.225, 2);     //0.23
  comb.number.roundHalfUp(10.384, 2);    //10.38
  comb.number.roundHalfUp(10.386, 2);    //10.39
  comb.number.roundHalfUp(10.3869, 3);   //10.387
  comb.number.roundHalfUp(10.3861, 3);   //10.386
  comb.number.roundHalfUp(10.269019, 5); //10.26902
  comb.number.roundHalfUp(-2.384, 2);    //-2.38
  comb.number.roundHalfUp(-2.385, 2);    //-2.38
  comb.number.roundHalfUp(-2.386, 2);    //-2.39
  
  @param {Number} num the number to round.
  @param {Number} precision the number of places to round to.
  @static
  @memberOf comb.number