Enable gossip encryption (#14640)

* Enable gossip encryption

* Fix order

* Auto-generate key

* Update gorp fork to include BeginTx

* Add a test for InsertIfExists

And point gorp to a custom branch for now

Co-authored-by: mattermod <mattermod@users.noreply.github.com>

model/system.go

@@ -19,6 +19,7 @@ const (
 	SYSTEM_POST_ACTION_COOKIE_SECRET      = "PostActionCookieSecret"
 	SYSTEM_INSTALLATION_DATE_KEY          = "InstallationDate"
 	SYSTEM_FIRST_SERVER_RUN_TIMESTAMP_KEY = "FirstServerRunTimestamp"
+	SYSTEM_CLUSTER_ENCRYPTION_KEY         = "ClusterEncryptionKey"
 )
 
 type System struct {