Cache partitioner groups
Skip product discounts
Remove delivery caching
Use the delivery classes as proxy for items groups
Remove all delivery functionality from cart
Improve delivery form
Use delivery wrappers in checkout groups
Get existing tests to run
Don't implement both __str__ and __unicode__
Show proper delivery method in summary
Pass storage variable to step
Improve checkout storage, remove groups

Now steps contains groups
Remove unnecessary name from delivery classes
Use the get_storage method in checkout
Fix checkout tests
Remove unnecessary checkout instance from steps
Fix tests
Fix adding to order, clean some code
Merge branch 'total-price-includes-correct-shipping-method'

Conflicts:
	saleor/checkout/forms.py
	saleor/checkout/steps.py