* Refactoring questions asked of user
In this pull request, I'm extracting and normalizing role-based
questions asked of the user.
Prior to this commit, our codebase has asked two very similar questions
of our user model:
- `user.has_role?(:admin)`
- `user.admin?`
In asking `has_role?(:admin)` we are relying on implementation details
of the rolify gem. In addition, the `has_role?` question asked
throughout controllers or views means that it's harder to create
hieararchies of permissions.
In favoring `user.admin?` as our question, we can use that indirection
as an opportunity to discuss and decide "Should someone with the
`:super_admin` role be `user.admin? == true`?"
The details of this commit is to do three primary things:
1. Ask the `has_role?` questions in "one place" in the code (e.g. the
`Authorizer` module)
2. Extract the role based questions that are on the `User` model and
provde backwards compatable delegation.
3. Structure the code so that it's harder to accidentally call
`user.has_role?` (e.g., make `User#has_role?` and `User#has_any_role?`
private).
This is related to #15624 and the updates are informed by discussion in
PR #15691. This commit supplants #15691.
* Refactoring the liquid tag policy tests
* Fixing typo
* Bump for travis
