Fix SelectState
Merge pull request #1 from djhaskin987/master

Fix SelectState
Added EditStorageGroup and made a few changes. Notably, Quantities now have integers for count, rather than just one.
Merge branch 'EditProductGroup' of https://github.com/djhaskin987/snake into EditProductGroup
Implemented AddItemBatchController and AddProductController
Made enableComponents() work properly in AddItemBatchController and AddProductController. Fixed three misspellings of 'of' in NonEmptyString.
Merge branch 'master' into EditProductGroup

Conflicts:
	src/gui/inventory/InventoryController.java
	src/model/IProductContainer.java
	src/model/ProductContainer.java
	src/model/ProductGroup.java
	src/model/StorageUnit.java
	src/model/StorageUnits.java
Fixed merge
Merge branch 'master' into EditProductGroup

Conflicts:
	src/gui/inventory/InventoryController.java
	src/model/StorageUnit.java