Attached new patch impl:
addressing issues raised:
- Adding new services should not usually require a change to core. In this case the Kerberos realm has been added to the cluster spec class. I wonder if there's a way to avoid that, e.g. with whirr.env properties?
The Kerberos realm could be provided as a whirr.env variable, but I thought it significant enough to warrant its own cluster spec field since it is a cross cutting concern (multiple modules are likely to use it, eg kerberos, whirr-cm, etc) and the additional meta-data (eg description, type) self document the important property. Having said that, I am happy to drop the cluster spec field in favour of whirr.env if we think we should?
- KerberosBaseHandler has an empty catch block (needs a comment at least), and the if statement should have braces.