Monkey patch 'django.utils.translation'

Modify Django's translation library, such that the gettext family of
functions return an empty string when attempting to translate a
falsey value. This overrides the default behavior [0]:
> It is convention with GNU gettext to include meta-data as the
> translation for the empty string.

This patch provides a holistic solution to replace the current piecemeal
approach [1][2].

Affected Methods:
    - gettext
    - ugettext

[0] https://docs.python.org/2.7/library/gettext.html#the-gnutranslations-class
[1] bad803e451ce63b4693ecf52b66cedfce5b43160
[2] https://github.com/edx/edx-platform/pull/4653
change PaidCourseRegistration.contained_in_order

now handles cases where the order has both a PaidCourseRegistration
and a CertificateItem
Remove i18n from ux reference templates
Studio: adding in usage note to UX reference templates
Merge pull request #4950 from edx/sarina/fix-18n

Remove i18n from ux reference templates
bumping bok choy version

check firefox version, raise exception with instructions for updating
Improve test coverage for course groups
Merge pull request #4686 from Stanford-Online/stv/i18n/gettext

Monkey patch 'django.utils.translation'
Merge pull request #5012 from edx/jbau/fix-contained-in-order

change PaidCourseRegistration.contained_in_order
Merge pull request #4937 from edx/dan-f/improve-course-group-coverage

Improve test coverage for course groups
Fixed InvalidKeyError on change enrollment.
LMS-11132
update get_parent_location method to select non-orphan parents from multiple parents
STUD-2007
Merge pull request #4985 from edx/waheed/lms11132-fix-invalid-key-error-change-enrollment

Fixed InvalidKeyError on change enrollment.
Merge pull request #4805 from edx/zub/bugfix/std2007-jumptoid

update get_parent_location method to select non-orphan parents from mult...
Refactor verify course id decorator and fixed tests.
Merge pull request #5010 from edx/waheed/refactor-verify-course-id-decorator

Refactor verify course id decorator and fixed tests.
Merge pull request #4943 from edx/mvo/bumping_bok_choy_version

bumping bok choy version
enable cms autoplay video test