Don't show timezone tasks as changed every time.

`copy` module being used for setting UTC timezone
was showing changed every time.  Replace it with a template,
which doesn't show changed unless it actually changes.

The motivation here is to strive to prevent false-positive reports
of changes so that changes are noteworthy and are not ignored by operators.
Don't show false changes on memcached /nonexistent task.

Report changed only when it has changed, by using
`file: state=absent` vs. `shell: rm -rf`
Merge pull request #200 from blueboxgroup/less-false-changes

Less false changes