* Implemented: logon to interactive shell with permission entry

* Implemented: logon to interactive shell with permission entry (e.g. firefox)

  issue #55, also simplified unneeded function code: issue #56

Also added a note/example that one can pass on arguments to `subuser run programs`   I did not know that before

e.g. with permission set

```
workerm@notebook:~$ subuser run firefox --container
root@cb31ffe9fb16:/# 
```

No permission set (default)

```
workerm@notebook:~$ subuser run libx11 --container
<libx11> has no permission to logon to shell
workerm@notebook:~$ 
```