User inactive content, isEnabled flags

- updated all areas to adapt to changes in user preferences. Channel,
sub-channel and category settings now affect which content will be
returned by the API
- categories now include an isEnabled flag
- updated tests to check for new additions
- much greater commenting across the board
- Removed some legacy methods and calls
Merge branch 'user-inactive-content' into dev

Conflicts:
	web/app/Apiv1/Repositories/Articles/ArticleRepository.php
	web/tests/_data/dump.sql
	web/tests/api/ApiTester.php