Implemented methods and other changes

TrafficLight
- Changed atributtes to public
Crossing
- Added int tickCount
- Added method bool reset( )
Crossing 1 and 2
- Added case 0 to switch(_state)
- Implemented timeTick( )
Added properties and fixed errors

Implemented properties (getters and setters) for all protected
atributtes of the crossing classes and fixed typing errors
Properties of all variables on Street.cs
Properties of all variables on TrafficLight.cs
implementation of the constructor of street.cs
Merge branch 'master' of https://github.com/fontys/Pro-CSharp
Add constructors Crossing class

Add constructors for the TrafficLight and Street inside of the Crossing
class
Merge remote-tracking branch 'origin/ashish-car'
implement properties for file handler
changes during meeting

nothing much
Merge remote-tracking branch 'origin/Ali'
changes during meeting

fixed the "type of" parameter used in the street constructor calls
inside the Crossing abstract class
Resolve merge conflicts
Added prototype interface design

just added elements to form
Implemented/added methods in GUI and SimulationController

1- Slight changes in the form designer
2- Changes in GUI.cs:
- called constructor for _controller and set its Gui reference;
- added method string filePath(int n);
- added method string saveMessage(string title, string message);
- implemented buttons and menu items methods, and subscribed menu call
"close" to Window.Closing event;
3- Changes in SimulationController.cs:
- Added property for _gui;
- close, save, saveas, load, startSimulation, pauseSimulation and
stopSimulation, removeCrossing, selectCrossing, addCrossing,
setCrossingProperty, clearGrid,  methods changed from bool to string;
- implemented method close.
GUI and Controller implementations

1- Made all classes public (to solve accessibility problems) and
serializable.
2-Added method void refreshScreen(Grid copyOfGrid) in GUI.cs;
3- Added "make change" button and method to simulate modifications in
the grid.
4- In SimulationController.cs:
- Called constructor for _timer;
- Made action _onTimeTick public instead of private;
- Set default _state value to State.Stopped, and created a getter for
_state;
- Used method changeCrossingProperty to simulate modifications;
- Implemented start, stop and pause methods;
- Added method timerHasTriggered.
Save, SaveAs and Load implementation

also changed the "close" method.
Boilerplate code for Car.move()