Allow inheritance of `monitored` and `benchmarked`

[noahhl]

We like to establish a high level ApplicationJob in our apps that actual work-processing jobs can inherit from. To enable that, this pull request switches to using a cattr_reader to handle tracking of benchmark & monitor status so that we can declare those once on the ApplicationJob.

(tests fail both on master and on this PR, but we're using this on a real app with results as expected)

[seuros]

I will test it and merge it asap. Thank you for your contribution