feature 7919 - Subscription API for OSS/BSS management systems

Delete_extra used to remove mapped_subscription
Moved code to use db.create_list function
Addressed review comments.

Change-Id: I84bd39e9a9c942d15762d4715843c7c539842767
Signed-off-by: preethika.p <preethika.p@tataelxsi.co.in>
diff --git a/osm_nbi/engine.py b/osm_nbi/engine.py
index 8f70bb6..33d7791 100644
--- a/osm_nbi/engine.py
+++ b/osm_nbi/engine.py
@@ -30,6 +30,7 @@
 from osm_nbi.descriptor_topics import VnfdTopic, NsdTopic, PduTopic, NstTopic, VnfPkgOpTopic
 from osm_nbi.instance_topics import NsrTopic, VnfrTopic, NsLcmOpTopic, NsiTopic, NsiLcmOpTopic
 from osm_nbi.pmjobs_topics import PmJobsTopic
+from osm_nbi.subscription_topics import NslcmSubscriptionsTopic
 from base64 import b64encode
 from os import urandom   # , path
 from threading import Lock
@@ -59,6 +60,7 @@
         "nsis": NsiTopic,
         "nsilcmops": NsiLcmOpTopic,
         "vnfpkgops": VnfPkgOpTopic,
+        "nslcm_subscriptions": NslcmSubscriptionsTopic,
         # [NEW_TOPIC]: add an entry here
         # "pm_jobs": PmJobsTopic will be added manually because it needs other parameters
     }