Added config flags for the job queue to make it switchable

config options are in services:jobs:queue and are 'enabled,reportStats,reportInterval,maxWorkers,logLevel(info/debug),pollMinInterval,pollMaxInterval,queueCapacity,fetchCount.

This is slightly less efficient - potentially - because we do a select before inserting instead of ignoring the insert conflict. It's likely less efficient because I don't anticipate a ton of duplicates, although the analytics job can certainly result in that, which is where I'd expect the knex implementation to slightly win out.

Regardless, testing is a fucking nightmare with knex directly as we have to spin up a db and use a schema for the table. Let's go down that path later if we need the performance improvements.

- moved to a more appropriate location (integration tests from e2e-server)

It appears testUtils.setup MUST be called as before(testUtils.setup()); and doesn't work as an anonymous function with any consistency.

This was failing locally due to the local test db (in /tmp/ghost-test.db) missing migration columns. Not sure why. It could be due to version mismatch at this point as the migration needs to be updated before merging this. Blowing away that file and then re-running init'd a table with the correct schema.