[GENERAL]: signals for completed registrations

[StevenHosper]

Currently, completed registrations are not translated to visible items within the overview.
This can cause quite some confusion.

The cause is as follows: new registrations result in an upload_task. Upon completion, no registrations are made within gmw/gmws gmw/monitoringtubes gmn/gmns or anything.

As a result, the query for the user-interface won't include the new registrations.

Within the signals.py file, we are able to create an action that would post to these endpoints once on the following conditions:

1. the registration type is 'registration'
2. the sourcedocument type is in: [GMW-Construction, GLD-StartRegistration, GMN-StartRegistration, FRD-StartRegistration].
3. the status is completed.
4. a BRO-ID is available.

If all of these are met, a post request can be completed.

Eventually new registrations should result in updates, but this is quite complicated.