Fix cache helper test.

Previously disguised as "ApplicationTest" in "models".
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Fix code styling.
Fix test for pool controller

- add js support for `access_denied`
- pool operations now require login
- append redirect url to login redirect expectation
- fix up deprecated queries
- sequence is now a string
Fix most(?) of deprecations in PoolController.

- add wrapper for sql generator thingy to match new rails
- fix old query syntax