1.**Print statement wrapped in a semaphore**, to control printing to the console.
(There is a possibility that the console print position could be changed if the currently printing thread was interrupted)
2. Added a `queueInteraction` semaphore to the `floor_info` struct. The idea of this is that only one lift-call button can be pressed at a time; this prevents more than one person in the queue interacting with the lift.
3.`addToStop` added to the `lift_thread` - this semaphore communicates if the lift is currently adding someone. Used primarily to prevent the lift moving while still loading someone (which would cause an non-loaded person to be unloaded). Very unlikely that this would occur, due to the number of statements that need executing first, but still could potentially occur
4.`targetLiftSelect` allows a lift to set itself as the target lift on a specific floor for a person thread. The person thread releases this semaphore when they load.
### Added Variables:
1.`targetLift[]` added to keep track of the currently set target lift for a floor. Used in conjunction with semaphore `4`.
### Other Changes:
1. Added a `POPULATION` preprocessor definition that will print the current counts of people on each floor, and the current floor positions of all people threads. Useful for detecting if someone is stuck.
