Integration Request 5

### Possibly breaking changes

- `swid_measurement` API endpoint has been moved to `swid-measurement`
- `swid-measurement` and `swid-add-tags`: Request data should now be submitted in a `data` param: `{"data": [...]}` instead of sending the JSON list directly
- Default users have been removed. Add them using `./manage.py setpassword`
- Root user has been removed. If you want one, add it using `./manage.py createsuperuser --database meta`
- API now requires basic auth, the user must have the `is_staff=1` flag set or the `front.write_access` permission assigned (-> the `admin-user` has that permission by default)
- SWID import now behaves as follows:
  - Import via management command: Trying to create an already existing tag will replace all tag attributes.
  - Import via API: The tag will not be changed and will be reported as already existing.
  - In any case, if the entity name changes, it will be updated in our database. The raw SWID XML (for previously existing tags) stays unchanged and still contains the old entity name.

### New features

- API fields are now filterable using the `fields=` param (see c9c4687)
- It's now possible to add package versions from the GUI
- It's now possible to add files from the GUI
- SWID Inventory has been revised
- AJAX loading indicators have been added
- Search strings in paging filters are now highlighted in the search results
- Some small changes were made to the models to allow `./manage.py syncdb` on MySQL
- Enabled non-interactive mode on setpassword command
- Paging for dynamic tables
- Added paging to potentially large tables everywhere

### Fixes

- Fixed most recent session in device report
- Some UTC-related bugs have been fixed
- It's now possible to show the inventory or log of a single day
- Fixed issue with search string urlencoding in pagings
- Many other small fixes