Surface user management via API client

[lo-chr]

Is your feature request related to a problem? Please describe.
I regularly want to create (and manage) users, via API, because I don't have direct CLI access to the server which hosts timesketch.

Describe the solution you'd like
I would like to have a feature, where I can create, list and modify users, when I have admin privileges within timesketch.

Describe alternatives you've considered
There is a feature that exists in tsctl, however, that limits user management to the time sketch server, prohibiting administration via API.