Adds a permission check to view Billing Entities (BE) before rendering the add/edit buttons for Organizations
Adds an input in the add/edit Organization form to select the BE
Refactor some internal code
Checklist
[x] Categorize the PR by setting a good title and adding one of the labels:
bug, enhancement, documentation, change, breaking,
as they show up in the changelog
[x] Update tests.
[x] Link this PR to related issues.
[x] Clear situation with first-login-dialog regarding the new permissions required.
Summary
Part of #438
Checklist
bug
,enhancement
,documentation
,change
,breaking
, as they show up in the changelog