Now that inputs can be relatively easily validated against
the schema this should also be used for all the "good" test
inputs to ensure that all tests test against valid inputs.
This commit implements the `reboot` option for kickstart files.
Note that there are two ways this can be enabled via the json.
Either via a boolean or by passing a dict with options.
```
{"reboot": true}
{"reboot": {"eject": true, "kexec": true}
```
Passing the empty dict
```
{"reboot": {}}
```
is not allowed by the schema.
Add functional/regression around the schema validation for the
kickstart stage. The goal is to ensure that the regexp matching
in the schema allows the expected uses and rejects clearly
forbidden ones.
