Introduce simple Identity Management API

[daniel-mader]

Description

The management features of the identity used for interactions should be extended to:

• „Create“ an identity: equivalent to producing a document for a given method. If the creation requires additional steps (such as funding), a response should be given that guides the caller on what to do next.
• „Delete“ the identity: equivalent to removing the document from the given network, resp. „deactivating“ serving the document for deterministic methods
• „Update“ the identity: equivalent to adding & removing a key. For deterministic methods (single key), this method should be rejected. „Key rotation“ could be treated as a single transaction of removing an existing key and adding a new key.

Motivation

Enhanced control over the identity used

Resources

No response

To-do List

• Create/Activate
• Delete/Deactivate
• Update