Add two models used for config options, for organization and project
Move helper function that creates the dwarsprofiel availablemeasurementtype to models
Add per organization and per project config options, and a screen to edit the project options
Add several new checks that depend on config options
Foutmeldingen aangepast zodat zo zoveel mogelijk de ingestelde waarden laten zien in de foutmelding
Remove the organization's allow_non_predefined_locations setting - we use configuration for that now.

Make choosing errors for an organization in the admin interface easier.
Preparing release 1.15
Back to development: 1.16