Fixed speed displayed in table view

#story [17]

src/main/java/seng302/Model/Boat.java

@@ -21,7 +21,7 @@ public class Boat {
      */
     public Boat(String name, double velocity, String abbrev) {
         this.velocity = velocity;
-        this.velocityProp = new SimpleStringProperty(String.valueOf(velocity* 1.94384));
+        this.velocityProp = new SimpleStringProperty(String.valueOf(Math.round(velocity)));
         this.abbrev = abbrev;
         this.name = new SimpleStringProperty(name);
     }