* adds Revocation model to interventions/models.py
* adds revocations to interventions detail view
* fixes duplicated ids in html includes
* refactors controls for detail view into included template files (controls.html)
* reduces max length for payment transfer notes from 1000 to 200
* adds RevocationAdmin to intervention/admin.py
* adds new form for adding a Revocation to an intervention's legal_data
* only one revocation per intervention possible
* removes add button in case of an existing revocation
* adds revocation routes to intervention app
* renames document field in Document model into file for more clarity
* adds/updates translations
* adds access_token as new attribute
* adds generating of access_token
* adds new form
* adds two new routes for sharing an intervention
* adds translation
* adds render_submit to BaseModalForm which triggers rendering the modal footer
* adds related object overview in detail view
* adds comment field to payment model for 'Verwendungszweck'
* simplifies intervention urls
* adds translations