Remove explicit paths to page for adding boards

Add a step that implements "When I go to add a board" instead of
using 'When I go to "node/add/board"'.  This makes the language
of the steps consistent with the changes in
c86ffbd94fa3eacf25b9a5d6e0485a04c8018b45, makes the tests more
readable, and makes them less brittle if we place the canonical
page for adding things somewhere other than ``node/add/*``.

Addresses #3484
Add tests for access to CRUD pages for Person content

The tests for editing content created by clerks in the same city
fail because there's no explicit relation to a shared group.
Perhaps the best solution is to make people group content.

Addresses #3484