Comment 4 for bug 1733881

@adconrad you are wrong,
If i set my timezone via timedatectl to Europe/Berlin, I get:

dev-t@pi3:~$ cat /etc/timezone
Europe/Berlin
dev-t@pi3:~$ ls -l /etc/timezone
lrwxrwxrwx 1 root root 22 Nov 27 05:24 /etc/timezone -> /etc/writable/timezone

dev-t@pi3:~$ date
Mon Nov 27 17:16:18 CET 2017

dev-t@pi3:~$ ls -l /etc/localtime
lrwxrwxrwx 1 root root 23 Nov 27 05:24 /etc/localtime -> /etc/writable/localtime

dev-t@pi3:~$ timedatectl
      Local time: Mon 2017-11-27 16:16:05 UTC
  Universal time: Mon 2017-11-27 16:16:05 UTC
        RTC time: n/a
       Time zone: n/a (UTC, +0000)
 Network time on: yes
NTP synchronized: yes
 RTC in local TZ: no

dev-t@pi3:~$ ls -l /etc/hostname
lrwxrwxrwx 1 root root 22 Nov 27 05:24 /etc/hostname -> /etc/writable/hostname
dev-t@pi3:~$ hostnamectl
   Static hostname: pi3
         Icon name: computer
        Machine ID: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
           Boot ID: XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
  Operating System: Ubuntu Core 16
            Kernel: Linux 4.4.0-1077-raspi2
      Architecture: arm