feat: support multisite switch via domain name

[wesleyboar]

Overview

Allow switching between multiple sites via domain name.

Related

Idea for a solution to TUP-706.

Changes

• added middleware
• added example settings for middleware

Testing

0. Be able to access a server at multiple domains e.g.
   • https://0.0.0.0:8000 and https://localhost:8000
1. In custom_app_settings.py, add new middleware to CUSTOM_MIDDLEWARE e.g.

   CUSTOM_MIDDLEWARE = ['taccsite_cms.middleware.settings.SiteIdMiddleware']

2. Set current CMS SITE to one of those domain names e.g.
   • Domain name: 0.0.0.0:8000
   • Display name: 0.0.0.0:8000
3. Create new CMS SITE with the other domain names e.g.
   • Domain name: localhost:8000
   • Display name: localhost:8000
4. Visit 0.0.0.0:8000.
5. Create/View a unique page.
6. Visit localhost:8000.
7. Create/View a unique page.
8. Switch between the sites using URL.
9. Verify each site only shows its unique page.

Note

You may need to reload page after site/domain switch to refresh the CMS toolbar output.

UI

Sites (Admin)	0.0.0.0:8000	localhost:8000

multisite.via.domain.mov