Deploy on BTP (#793)

minimal changes required to deploy the CAP samples in _shared db_ mode:
- db: all bookshop, orders, reviews CDS models into one db instance (_shared-db_)
- services: bookstore, orders, reviews
- approuter with UI symlinks:
  - Vue: bookshop, reviews
  - Fiori: orders
 - authentification: xsuaa
 - messaging: Event Mesh
 - destinations: orders, reviews
- cds:
  - projection OrdersNoDraft for backend direct access
  - event OrderChanged
- deployment: mta.yml

package.json

@@ -25,6 +25,9 @@
     "semver": "^7"
   },
   "scripts": {
+    "build": "mbt build -t gen --mtar mta.tar",
+    "deploy": "cf deploy gen/mta.tar",
+    "undeploy": "cf undeploy capire.samples --delete-services --delete-service-keys",
     "bookshop": "cds watch bookshop",
     "fiori": "cds watch fiori",
     "lint": "eslint",