Added TestStock and TestSupplier classes,
Stock update: changed StockLevels method
Changed Product to only have name and supplier price.
Changed Stock to be a subclass of Product
Merge branch 'christine' of https://github.com/fcpteam1/project into
christine

Conflicts:
	.classpath
	src/Product.java
	src/Stock.java
	src/StockTest.java
	src/Supplier.java
	src/SupplierTest.java
Removed duplicate methods from merge
StockGui added
Fixed stockLevels method to get total of duplicate stock items
Changes to product and Stock.stockLevels
Merge branch 'master' into christine

Conflicts:
	src/Controller.java
	src/MainMenuGUI.java
	src/Product.java
	src/Stock.java
	src/Supplier.java
Changed stockGui to include button to remove out of stock items
Changes to createSale in Shop and createSaleOccured in saleMainPanel
Merge branch 'christine' of https://github.com/fcpteam1/project into christine
Adding a table to the Stock Tab to display stock.
Button for all stock, and button for stock listed by date.
Adding edit price functionality to table.
cp
Merge branch 'christine' of https://github.com/fcpteam1/project into
christine

Conflicts:
	.classpath
	orders.ser
	sales.ser
	src/GUI/SaleMainPanel.java
	src/GUI/StockGUI.java
	stocks.ser
Error checking class
SupplierGUI Error checks
Changed Stock tab's layout to match other tabs
Stock Tab now the same as other tabs.
added chart button to stock tab
ser files fixed
fixed bug in stock prediction panel with column names