Added Breno Uchoa to AUTHORS
Merge
Revert cart to old values if update is not valid
Show invalid quantity in stock error in cart update, in prep for pr that resets cart form values.
Mark up cart errors for correct styling.
Merge
Maintain errors when creating new cart formset when cart update invalid.
Fix non-ascii chars in product option names. Closes #112.
Increase cart item url size to allow for potentially long unicode slugs. Closes #113.
Fix handling of 'same shipping details' checkbox.
Pep8 fixes and remove redundant dict copy.
Remove redundant import.