When doing import, we ran into an issue where there was a learner with an external program key that was the
same as an existing, completely unrelated edX account username. Rather than try to guess which learner we want
or do the lookups backwards, it seemed that splitting these columns to avoid any ambiguity would be the most
straightforward and simple approach
* Generate common/djangoapps import shims for LMS
* Generate common/djangoapps import shims for Studio
* Stop appending project root to sys.path
* Stop appending common/djangoapps to sys.path
* Import from common.djangoapps.course_action_state instead of course_action_state
* Import from common.djangoapps.course_modes instead of course_modes
* Import from common.djangoapps.database_fixups instead of database_fixups
* Import from common.djangoapps.edxmako instead of edxmako
* Import from common.djangoapps.entitlements instead of entitlements
* Import from common.djangoapps.pipline_mako instead of pipeline_mako
* Import from common.djangoapps.static_replace instead of static_replace
* Import from common.djangoapps.student instead of student
* Import from common.djangoapps.terrain instead of terrain
* Import from common.djangoapps.third_party_auth instead of third_party_auth
* Import from common.djangoapps.track instead of track
* Import from common.djangoapps.util instead of util
* Import from common.djangoapps.xblock_django instead of xblock_django
* Add empty common/djangoapps/__init__.py to fix pytest collection
* Fix pylint formatting violations
* Exclude import_shims/ directory tree from linting
* Edit team manage to check sizes at end of import
* Fix size validation to take new teams into account
* Remove redundant max size check
* Consolidate team membership counters
* Remove unused user_ids_by_teamset_id set
* Fix team removal to only occur after validation
* Update team full error message
* Prefetch users when looking up team counts
* Check learner enrollment status to avoid mixing learners from incompatible tracks (e.g. masters/audit) to the same team
* When a new team is encountered on a team management CSV, create it with the protection status of the user
