code: function ( positions ) {
              if ( $B.isArray(positions) && !$B.isEmpty(positions) ) {
                  this._startValue = positions[0].min;
                  this._endValue = positions[positions.length - 1].max;
                  this._positions = positions.concat([]);
              }
              return this;
          }
docs: ==================== Public Methods ==================== // 
  포지션 데이타 갱신
  @param   {Array} positions   포지션 데이타 배열, [{min:Number, max:Number, data:*}, ...