ENG-8400.

Handler which updates Tunnelbroker device token using socket connection.

Depends on D12537, D12524

Tested both web and native:

1. Login.
2. Opening & closing app / refreshing app.
3. Manually changing device token to make sure this is triggered and executed only once.
4. Tested case when user logs out, Identity log out fails (D12525 is not executed), and then when user logs in device token is assigned only to the new deviceID (assuming device token did not change).