Whitespace.
Updating Expansion docstring.
Cleaning up Expansion.add_property() styling.
Updating broken link in Resource docstring.
Updating Resource attributes order.
Rearranging some declarations.
Whitespace.
Fixing style.
Updating some comments.
Whitespace.
Whitespace.
Whitespace.
Whitespace.
Whitespace.
Whitespace.
Whitespace.
Whitespace.
Updating StatusMixin docstring.
Updating CollectionResource docstring.
Rearranging CollectionResource attributes.