changing lane

[arvindshekar07]

changing lane to be added in the code.
at line 277 to 282

if (too_close) {
   //try and change lanes
  bool canMergeLeft = lane > 0;
  bool canMergeRight = lane < 2;
  //try merging left
  int ref_lane = lane - 1;
  if (canMergeLeft && d < (2+4*ref_lane+2) && d > (2+4*ref_lane-2)) {
          if (abs(check_car_s - car_s) < 20) {
              canMergeLeft = false;
          }
  } 

   //try merging right
  ref_lane = lane + 1;
  if (canMergeRight && d < (2+4*ref_lane+2) && d > (2+4*ref_lane-2)) {
      if (abs(check_car_s - car_s) < 20) {
           canMergeRight = false;
      }
}
}
if (canMergeLeft) {
  lane--;
} else if (canMergeRight) {
  lane++;
  }