Consider merging Archiver and QA

QA has a dependency on Archiver, and won't/can't run without it. Set-up for both is spread across two different locations and requires flipping back and forth. There's nothing to be gained from ckanext-qa existing separately from ckanext-archiver. It may even simplify the task setup with celery.

There's also a clear workflow
1. Download the resource,
2. Check the QA,
3. Update the resource

Where the resource is local there's probably no need to download it. QA should be turn-off-able.

Start by mapping the setup and dependency between ckanext-qa and ckanext-archiver, including the Celery task configuration mentioned in the issue. Define the intended download, QA, and resource-update workflow, including local-resource handling and disabling QA. Done requires an agreed integration design and corresponding implementation scope.

Written by the indexing model from the issue text.