Add ready conditon and cleanup finalizer and status patching (#186)

This change adds a ready condition. It also sets a standard for status
fields and documentation. It makes use of helper functions from FluxCD
to better manage patching of finalizers and status.

Signed-off-by: Philip Laine <philip.laine@gmail.com>

examples/refactor/setup-key.yaml

@@ -4,4 +4,4 @@ metadata:
   name: test
   namespace: default
 spec:
-  expiration: 0
+  ephemeral: true