Return $metadata resource as odata + openapi spec

Returning odata and openapi specs in json format.
Specs are scoped to the request permissions.
Different users (roles) will receive different metadata endpoints
and resources.

Change-type: minor
Signed-off-by: fisehara <[email protected]>

Author: fisehara

package.json

@@ -55,6 +55,7 @@
     "express-session": "^1.17.3",
     "lodash": "^4.17.21",
     "memoizee": "^0.4.15",
+    "odata-openapi": "^0.19.1",
     "pinejs-client-core": "^6.12.2",
     "randomstring": "^1.2.3",
     "typed-error": "^3.2.1"