Add age column and fix column order

[jstudler]

A few UX changes:

• Adds an age column (with Kubebuilder this disappears from the CRD as soon as you add the first printcolumn)
• Orders the condition columns to feature the "Ready" condition as the last one

Before:

kubectl get ipc
NAME                    IPADDRESS    READY   IPASSIGNED
ipaddressclaim-sample   2.0.0.1/32   True    True

After:

kubectl get ipc
NAME                    IPADDRESS    IPASSIGNED   READY   AGE
ipaddressclaim-sample   2.0.0.1/32   True         True    4s

[alexandernorth]

lgtm!