Feature Request: Provide Websocket Interface as Cmd Option

[erikzenker]

Problem:
The websocket is currently bound to all interfaces on 0.0.0.0 and with #23 also to 127.0.0.1 by env variable. One might bind the websocket to a particular interface without further software.

Solution:
Provide a command line option e.g.: -i 0.0.0.0 which leaves the configuration of the interface up to the user.