Move backend app templates to be installed from configmap volume (#1331)

Instead of adding the app templates launched from the backend via
`backend/btrixcloud/templates`, add them to a configmap and mount the
configmap in the same location.

This allows these templates to be updated, like other values in
charts/... without having to rebuild any of the images, speeding up dev
and maintenance time.

Changes include:
- move backend/btrixcloud/templates -> chart/app-templates/
- add app-templates/*.yaml to app-templates configmap
- mount app-templates configmap to /app/btrixcloud/templates/ in api and op containers

chart/templates/backend.yaml

@@ -41,6 +41,10 @@ spec:
           secret:
             secretName: storages
 
+        - name: app-templates
+          configMap:
+            name: app-templates
+
       containers:
         - name: api
           image: {{ .Values.backend_image }}
@@ -61,6 +65,9 @@ spec:
             - name: storages
               mountPath: /tmp/storages/
 
+            - name: app-templates
+              mountPath: /app/btrixcloud/templates/
+
           resources:
             limits:
               memory: {{ .Values.backend_memory }}
@@ -129,6 +136,9 @@ spec:
             - name: storages
               mountPath: /tmp/storages/
 
+            - name: app-templates
+              mountPath: /app/btrixcloud/templates/
+
           resources:
             limits:
               memory: {{ .Values.backend_memory }}

chart/templates/configmap.yaml

@@ -128,11 +128,8 @@ data:
 apiVersion: v1
 kind: ConfigMap
 metadata:
-  name: nginx-config
+  name: app-templates
   namespace: {{ .Release.Namespace }}
 
 data:
-{{ (.Files.Glob "*.conf").AsConfig | indent 2 }}
-
-#{{ (.Files.Glob "frontend/*.*").AsConfig | indent 2 }}
-
+{{ (.Files.Glob "app-templates/*.yaml").AsConfig | indent 2 }}