Upgraded gems
Making tests pass.
Add controller behavior to test that controllers are secured with SOrcery

- act as as 'protected action'
Cleaning up the way the ladder renders.

- the ladder no longer renders divs for 'pages' zero and last + 1
- added tests for this
Volume validates that numerb of pages is divisible by 4

- created a DivisibleByValidator.
- Can't use shoulda validation matchers on models with virtual attyributes
  so I wrote custom tests for those validations

[Finishes #54949996]
Show structural components on the ladder.

- outlined signatures
- highlighted flats
Merge branch 'feature/54949996-volume-divisible-by-4' into develop

[Finishes #54948374 #54948382]