Categories menu + navigation changes
Merge remote-tracking branch 'origin/Development' into Dev

Conflicts:
	app/src/main/java/yorgi/gierkrowka/MainActivity.java
	app/src/main/java/yorgi/gierkrowka/adapters/MenuItemsAdapter.java
	app/src/main/java/yorgi/gierkrowka/fragments/menu/MenuCategoriesFragment.java
	app/src/main/java/yorgi/gierkrowka/fragments/menu/MenuItemFragment.java
	app/src/main/java/yorgi/gierkrowka/models/MenuItem.java