* Handle timezone updates on Ubuntu 16.04+ on containers
Although Ubuntu 16.04 will use timedatectl by default,
containers without a working timedatectl need to use the
old method.
A bug in Ubuntu for the old method means having to write
a nasty hack
https://bugs.launchpad.net/ubuntu/+source/tzdata/+bug/1554806
* Add tests for timezones
Ensure timezone changes work across various OSs
Will Thames