The `type: :feature` is automatically detected by RSpec because these
tests are inside the `spec/features` folder. Using `feature` re-adds a
`type: :feature` to these files, which will result in a conflict when we
upgrade to Rails 5.1's system tests.
Because of this change, we also need to change `background` to `before`
or else these tests will fail.
allows managers to create users without email
hides email preferences from account page for email-less users
prevents email delivery to users with no email
adds spec for user creation from management
adds specs for user's email requirement
adds spec for no deliveries if no email
