Upgrade to Django 1.8.5

Quieted noisy logging statement

The majority of our course seats will not have a credit provier set. This logging statement is only useful when developing for credit locally. It's severity has been appropriately decreased.

ECOM-2477

Logging JWT authentication errors

JWT authentication errors get squashed by DRF. Logging these errors during development will help quickly identify configuration issues and other potential causes of the errors.

ECOM-2477

Ignoring generated docs

ECOM-2474

Change the structure of API views implementation

ECOM-2338

Text improvement on credit checkout page

ECOM-2339

Use JWT auth for ecommerce workers.

Adds a superuser which the ecommerce worker can use to authenticate
against the service. Also introduces changes to allow multiple JWT
issuers to be used.

ECOM-2331

Update SKU Generation

ECOM-2237

Clean up README

Create new docs sections for asset pipeline and email notifications, extend existing sections with content from README.

Bump version of segment's analytics-python package to 1.1.0

Move acceptance testing documentation to the docs directory

Make acceptance tests compatible with async fulfillment

Acceptance tests check a configurable number of times for an order's completion before failing. ECOM-2248.

Improve the acceptance testing experience

Cleans up and updates acceptance testing documentation, gives environment variables better names, fixes an issue preventing LMS registration and enrollment from being tested locally, and makes testing of the CyberSource payment flow optional. Prelude to ECOM-2248.

Added script to create publish_course_modes_to_lms switch

This switch is needed for a proper integration with LMS. Creating it via migration means one less step for setup. Also, updated tests to toggle switches in a simpler manner.

Removed devstack overrides

- Retrieving base settings from configuration
- Allowing for local overrides in private.py
- Using dev logging

Removed docs compilation from Travis

Compiling docs after validation breaks coverage reporting.

Asynchronous order fulfillment

Prepares Otto for asynchronous order fulfillment by initializing a Celery app on startup; Celery tasks are executed locally for development. Also modifies the order fulfillment API endpoint to allow initial fulfillment attempts, not just retries. ECOM-2242.

Documentation Update

- Copied requirements and basic documentation from the IDA template
- Testing docs build in Travis

Updated loading of private settings

The previous implementation of private settings loading hid bugs in private.py. This implementation ensures those issues prevent the service from being run.

Upgrade to Django REST Framework 3.2.3