Eliminated unnecessary ServiceLocator/ConfigReader in VuFind\Cart; dependencies and configuration are now injected through constructor.

Added CollectionSideFacets recommendation module and set it up to be active by default in collection view.

Made record router smart enough to figure out collection links even if not given a full record driver object.

Made record router a service rather than a static class to enable dependency injection and easier overriding.

Revised Solr Tree Data Source to use record drivers instead of direct array access to Solr response.

Created collection controller; for starters, just an extension of AbstractRecord with a few minor changes and some cloned Solr Record templates.

made Authority module more robust by standardizing routing.

- Decoupled record drivers from tab rendering
- Every record tab now has a corresponding class and template
- Record driver => tab mapping is handled through module.config.php
- Added some missing comments to existing code

Switched to dependency injection for cleaner WorldCatIdentities/WorldCatTerms recommendation modules.