Added 'substract' buttons to player configuration.
Added Market generation to planets
Finished Planet Cargo Map

Methods for retrieving and updating data. Also a method to return map as
an array of objects
Initial set up for the marketplace UI.
Fixed Save, Load, Quit, and Retire buttons.
Modified Game.fxml and the controller UI.
Allowed Ship to interact with Market

Sorry for the delay, guys, I've been at a friend's Birthday Party.
Completed Game.fxml
Updated Player Class

Updates player class to include canTrade, canSell, trade, and sell
methods. Still needs to be fixed in order to work.
Added javadocs to Ship and Weapon
Fixed Ship.java
Implement global instances (Player, Ship, Planets,...) for the entire game.
Scrapped global instances Created local instances in GameController.
Added cargo API to Ship. Added money att. to Player. Updated GameController
Updated UI.
Added getters and setters for Ship cargo
Completed the marketplace feature for the game.
Fixed button bug.
Created planet price generators

Variance is only positive rather than positive or negative. Can be
implemented later. Methods to get prices for all goods or prices of
individual goods
Implemented 50% sell price.