* feat: System defined taxonomies
* style: models.py moved to models/base.py
* feat: New Content System defined models
* style: Lint and migration
* fix: Fix migration error
* chore: Rebase and compile requirements
* refactor: adds ContentTaxonomyMixin for use when creating content system taxonomies
Pulls the ContentTaxonomy-specific logic into a mixin class to bring
the Content-specific logic into other Taxonony subclasses.
* fix: Tests
* test: System defined model validations
* fix: Move language taxonomy creation to openedx-learning
* style: Rename of OrganizationSystemDefinedTaxonomy
* style: nits
* chore: Update openedx-learning dependency
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Co-authored-by: Jillian Vogel <jill@opencraft.com>
* refactor: moves is_content_creator
from cms.djangoapps.contentstore.helpers to common.djangoapps.student.auth
* feat: adds content tagging app
Adds models and APIs to support tagging content objects (e.g. XBlocks,
content libraries) by content authors. Content tags can be thought of as
"name:value" fields, though underneath they are a bit more complicated.
* adds dependency on openedx-learning<=0.1.0
* adds tagging app to LMS and CMS
* adds content tagging models, api, rules, admin, and tests.
* content taxonomies and tags can be maintained per organization by
content creators for that organization.
* feat: added notifications for discussions app
* feat: added unit tests for handler
* feat: updated openedx-events package
* fix: updated notification creation logic and tests
* refactor: updated openedx-event version and event name
* refactor: moved logic to separate methods
