Update aplus-auth to 0.2.0, add permission checks to views, add logging, fix custom template caching

[lainets]

Description

What?

Update aplus-auth to 0.2.0, add permission checks to views, add logging, and fix custom template caching.

Why?

Shortens JWT lengths, and increases security. Security logging was required. Templates wouldn't be reloaded after they were changed.

How?

Respond with 403 if the course key is an integer (i.e. it is the remote id) and the user has no access. Logging on endpoints where there could be an effect to the course. Remove caching of courses' custom templates.

Testing

What type of test did you run?

• [ ] Accessibility test using the WAVE extension.
• [ ] Django unit tests.
• [ ] Selenium tests.
• [ ] Other test. (Add a description below)
• [X] Manual testing.

Did you test the changes in

• [ ] Chrome
• [ ] Firefox
• [X] This pull request cannot be tested in the browser.

Programming style

• [X] Did you follow our style guides?

Have you updated the README or other relevant documentation?

• [ ] documents inside the doc directory.
• [ ] README.md.
• [ ] Aplus Manual.
• [ ] Other documentation (mention below which documentation).

Is it Done?

• [ ] Reviewer has finished the code review
• [ ] After the review, the developer has made changes accordingly
• [ ] Customer/Teacher has accepted the implementation of the feature