## Revert attributes changes from 13.7

Per <https://discourse.chef.io/t/regression-in-chef-client-13-7-16/12518/1> , there was a regression in how arrays and hashes were handled in 13.7. In 13.8, we've reverted to the same code as 13.6.

## Continuing work on `windows_task`

13.8 has better validation for the `idle_time` property, when using the `on_idle` frequency.

## Security Updates

- Updated libxml2 to 2.9.7; fixes: [CVE-2017-15412](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-15412)