added comments(stuff to change)

**number** is to show which other lines are related to the same issue.

some minor issues, biggest issue is that in some places this says PriorityQueue and other places are using LinkedList for the same object, need to find out which one is correct.

counter.clear should be counter.reset to fit with the already made counter class.

increment waiting time doesnt need a parameter (it just increases waiting time by 1)

other issues are just typos (writing Aircraft instead of AirCraft or putting the object reference on the wrong side (counter Counter instead of Counter counter)