rename djang-babel to enmarker
upgrade the reqs

- Updating Python Requirements
- Fix cache key generation to use class name and module

This was stringifying the class object directly, resulting in cache keys
like `:1:<class 'xblock_django.models.XBlockConfiguration'>.xblock_django.api.deprecated_xblocks`
which then cause breakage when Django 2.2.13 validates the keys.

Co-authored-by: edX requirements bot <testeng+edx-requirements-bot@edx.org>

* Updating Python Requirements

* Pin django-pipeline and lxml

Co-authored-by: Jeremy Bowman <jbowman@edx.org>

This reverts commit 1d7ff32a.

* Updating Python Requirements

* Constrain django-cookies-samesite until dep bug fixed

* Fix PEP 8 problems revealed by pycodestyle upgrade

Co-authored-by: Tim McCormack <tmccormack@edx.org>
Co-authored-by: Jeremy Bowman <jbowman@edx.org>

This adds contraints to:
kiwisolver: next release only works with python>=3.6

The was run to upgrade:
django-splash
django-wiki
edx-search
The previous versions were constraining django below 2.0.

Co-authored-by: Robert Raposa <rraposa@edx.org>

Remove duplicate constraints in requirements/constraints.txt uncovered by the recent change in pip-compile output format. I sorted the pinned dependencies by name to try and make it more obvious if this happens again. I also upgraded to pip-tools 4.5.1, which removes the line numbers from the enhanced pip-compile output added in 4.5.0, which should reduce future diff churn and merge conflicts but means that there's a large diff this one last time.

Also unpin edx-search again after the previous change to do that was apparently broken by a merge conflict.

Some tests that used to mock the cache internals of ConfigurationModels
had to be modified to use CacheIsolationTestCase instead (the things
they were mocking no longer exist).

Removing the moto.

This is step 3 of DE-1824.

Also update:
* six 1.13.0 => 1.14.0
* edx-django-utils 2.0.2 => 2.0.3
* skip test that checks all model changes have migrations.  (We defer
  this to step 4.)

* Switch make upgrade to Python 3.5

* bok-choy fixes, constrain django-debug-toolbar

* Remove flaky bok-choy test