Upgrade edx-enterprise package to 0.55.4.

https://github.com/edx/edx-enterprise/compare/0.55.1...0.55.4

Verify 'Full Name' field does not allow HTML.

Cale/latest edx lint

Fix warnings/errors in Django 1.10

Merge release back to master

PLAT-1418 Remove obsolete can_import_settings attribute

PLAT-1382 Populate ALLOWED_HOSTS for tests

Remove zendesk access token from support view.

TE-2320 - paver command to consolidate bokchoy db cache creation

Remove flaky Asset Task testcase classes 

PLAT-1801 Preserve new user login behavior under Django 1.10+

Move ACE Common code out of Schedules

Fix more registration form bugs.

Fix watch_assets call from paver update_assets.

Schedules: turn off HTML escaping for email text fields

Handle Unicode chars with AlreadyRunningError exception

'Full Name' field in the student account settings is allowing HTML
as an input which makes spoofing easily.To avoid it, validation is
added that ensures 'Full Name' field does not allow HTML as input.

LEARNER-3337

Changed AlreadyRunningError to be able to throw unicode error message, in case of accented characters resulted from language translation
EDUCATOR-1730

Learner-3399 fix for certificates

update ORA to 2.1.5

[ENT-751] Update the SailThru var with Enterprise learner information

updated translations

The client-specific JWT doesn't really make any sense and only causes issues due to needing to configure both. This change updates LMS to use the standard issuer.

LEARNER-3441

Schedules: Add celery task logging