[BB-2659] juniper update

BB-2659 juniper xblock html and xblock completable (#14)

* Update requirements

* Fix some pydocstyle errors

sort of.

* Update django version

Missed this as it didn:t cause obvious errors.

* Update the version number

* Comment on the requirement for Python 3.5

* Update requirements files

* Update the CircleCI configuration to use Python 3.5

* Fix a deprecation warning

ie, update render_template to render_django_template.

* Add setup instructions

* Install requirements in correct order

In order to avoid weird issues with django versions, the base requirements
need to be installed before the test and quality requirements.

* Fix an incorrect requirement

* Bump the major version

[BB-2120] Change default editor of excluded HTML5 block (#10)

v0.1.3

[BB-2120] Change default editor of excluded HTML5 block (#10)

[BB-2120] Create excluded HTML5 block (#9)

v0.1.2

[BB-2120] Create excluded HTML5 block (#9)

Substitute keywords (#8)

v0.1.1

[BB-1780] Substitute keywords (#8)

v0.1.0: Add "Allow JavaScript" Option (#5)

* Add `allow_javascript` option

* Add some basic test cases

* Add some scenarios

* Change `allow_javascript` scope to `content`

* Add tests docstrings

* Minor style improvements

* Fix xblock button actions not firing in settings page

* Fix invalid characters being shown in the editor

* Remove whitespace