Experimenting with passing vector to matlab by reference. Needed a rollback point.
Changed vecToMatlab and outputData to send data by reference instead of making a copy.

outputData now uses the system variable for the current user to save a file in the documents folder.
Added simulation 3 functions to Vehicle and main.

Vehicle: Added a constant brake force private member, added a brake() public function that calculates the vehicle's brakeing velocity and added a deccel private function to calculate the brakeing acceleration.

main: added simulation 3 function and plotting.