[Ajout] Structure de données Square

src/main/java/model/Square.java

+package model;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import util.Position;
+
+public class Square {
+    private List<Entity> entities;
+    private Position position;
+    public Square(Position position){
+        this.entities = new ArrayList<Entity>();
+        this.entities.add(new EmptySquare(position));
+        this.position = position;
+    }
+    public Square(Position position, Entity entity){
+        this.entities = new ArrayList<Entity>();
+        this.entities.add(entity);
+        this.position = position;
+    }
+
+    public List<Entity> getEntities(){
+        return this.entities;
+    }
+
+    public Position getPosition(){
+        return this.position;
+    }
+
+    public void addEntity(Entity entity){
+        entities.add(entity);
+    }
+
+    public void removeEntity(Entity entity){
+        entities.remove(entity);
+    }
+
+    public void setEntities(List<Entity> entities){
+        this.entities = entities;
+    }
+    
+}