e2e tests for editing and deleting contacts

[danjm]

We need to expand the functionality covered by our test/e2e/tests/address-book.spec.js

Currently, there are tests for adding a contact and sending to a contact.

We need to add tests for editing an already added contact and deleting an already added contact.

We should be able to use the 'address-entry' fixture. Add a separate it block, description string and withFixtures call for each of these cases. Appropriate assertions should be made against rendered text before and after editing and deleting.