This reverts commit 8b47af8b, reversing
changes made to c0055b3b.

Fix #737: delivering of local activities causing unintended side effects, such as rollbacking changes

Ensures federation urls can answer to application/ld+json, application/activity+json and application/json requests

Fix #706: Added a 'fix_federation_ids' management command to deal with protocol/domain issues in federation
IDs after deployments