## On Debian prefer Systemd to Upstart

On Debian systems, packages that support systemd will often ship both an old style init script and a systemd unit file. When this happened, Chef Infra Client would incorrectly choose Upstart rather than systemd as the service provider. Chef Infra Client will now prefer systemd where available.

## Handle the 'supports' property better

Chef Infra Client 13 removed the `supports` property from core resources. Chef Infra Client 12 was incorrectly giving a deprecation notice for another property called `support`, which prevented users from properly testing their cookbooks for upgrades.

## Don't crash if downgrading from Chef Infra Client 13 to 12

On systems where Chef Infra Client 13 had been run, Chef Infra Client 12 would crash as the on-disk cookbook format has changed. Chef Infra Client 12 now correctly ignores the unexpected files.

## Provide better information during failures

When Chef Infra Client fails, the output now includes details about the platform and version of Chef Infra Client that was running, so that a bug report has more detail.