Regression: Missing UTC (config-related)

[jnd-au]

With the latest unreleased Config feature (31f3810 and 2139f90), the default behaviour of tz has changed. In stable release v0.7.0, the default behaviour of tz (with no configuration) was to show Local and UTC timezones. But now: UTC is missing, and only the Local timezone is shown, yet the README.md documentation still says:

Run tz with no arguments to show the local time, as well as the UTC time zone.

So, this seems to be a bug. Also, this change of behaviour/configuration was added to tz without unit tests.