nut0: Add host Ignition config

*nut0.pyrocufflink.blue* is a Raspberry Pi 3 that will run `upsd` and
`upsmon` to monitor and control the UPS on the server rack.

nut0.yaml

@@ -0,0 +1,17 @@
+variant: fcos
+version: 1.4.0
+
+ignition:
+  config:
+    merge:
+    - local: fix-hybrid-mbr.ign
+    - local: common.ign
+    - local: zram.ign
+    - local: cfg.ign
+
+storage:
+  files:
+  - path: /etc/hostname
+    mode: 0644
+    contents:
+      inline: nut0.pyrocufflink.blue