* lint amnesty in teams,tests,survey and verify_student

* 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

EDUCATOR-5080 - Switched back to using topid_id in the method due to a cascade of test failures.  Added ticket to cover the refactor at a future time

EDUCATOR-5080 - Responding to code review comments, removed deprecated test, updated docstrings, fixed linting issue

EDUCATOR-5080 - Removed unused course logic, renamed method to refer to teamsets, updated docstrings, api and tests

 Add teamset type validation to has_specific_team_access

*allow users to join one team per teamset

EDUCATOR-4903. Move defaults to correct place - cr

* 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

interim commit

clean up

Initial unit tests and pylint

pylint cleanup

Unit tests extended and passing. Pylint

WIP - fix Unit tests extended and passing. Pylint

Updated logic to validate before commit.

CR pass1

CR pass1, pep8

pep8 2

interim cr

interim cr2

refactor to using DictReader

removed uneeded mixin

pr comments

encoding fix and return value

Cache teams/membershipos

ncr

cr aed

This will remove imports from __future__ that are no longer needed.

https://docs.python.org/3.5/library/2to3.html#2to3fixer-future

 This is needed so Masters learners will not be in the same team as verfied and audit learners. If the team is designated as organization protected, it will not be visible or accessible by verified or audit track learners
MST-34

MST-17

* Data migration: Alter CharField to SlugField for 2 fields in CourseTeam model

* For all files, from __future__ import unicode_literals.
* Add @python_2_unicode_compatible to both models.
* Test six.string_type(obj) for both models.

Also, fix some new pylint warnings and improve model repr methods.

MST-24

MST-6

Added the import statements

Django 2.0 will make this field required for `ForeignKey` and `OneToOneFields`.
In previous versions the option defaulted to `models.CASCADE` when not
specified. This change should make the deprecation warnings in the current
Django version go away.

The migrations where also modified, but the changes should not cause a change in
the database schema since `models.CASCADE` was already the old default.

- add edx.org to lms tests KNOWN_HOSTS
- Don't check CourseTeamMembership field mutability on creation

Please note that this is a squshed commit and the work of:
Symbolist, macdiesel, nedbat, doctoryes, muzaffaryousaf and muhammad-ammar

Also remove useless docstrings where they were added to keep pylint
quiet.

Also add a __repr__ to CourseTeam so that it could be useful too.