provision: use become instead of sudo

provision: move repo url and revision to vars

crud: use dict comprehension instead of dict() with generator expression

fruitbar: remove encoding declaration (not necessary, the code is ascii)

tests: check that _rev is present in output

ui: use dot operator to access known object properties

tests: pass data to create_resource() and update_resource() explicitly

tests: use assertIn() for searching for an id in response

crud: split a long line

provision: use supervisor's sensible defaults more