AppManager: Add API endpoint to install dodo app

Refactors cue definitions.

Next steps:
* Needs some cleanup, namespace is hard coded ...
* Maybe merge with regular install API
* Support exposing ports across clusters

Change-Id: Ibfc3c3f742b61f2c5874012fe6c77b958eae81d9
diff --git a/core/installer/values-tmpl/etherpad.cue b/core/installer/values-tmpl/etherpad.cue
index 980c5eb..a70b7cd 100644
--- a/core/installer/values-tmpl/etherpad.cue
+++ b/core/installer/values-tmpl/etherpad.cue
@@ -46,7 +46,7 @@
 		}
 	}
 
-	volumes: data: size: "1Gi"
+	volume: data: size: "1Gi"
 
 	postgresql: db: {
 		name: "db"
@@ -64,7 +64,7 @@
 					pullPolicy: images.etherpad.pullPolicy
 				}
 				portName: _httpPortName
-				persistentVolumeClaimName: volumes.data.name
+				persistentVolumeClaimName: volume.data.name
 				db: {
 					type: "postgres"
 					host: "postgres-db.\(release.namespace).svc.cluster.local"