PLT-6080 moving clustering to memberlist (#6499)

* PLT-6080 adding cluster discovery service

* Adding memberlist lib

* Adding memberlist lib

* WIP

* WIP

* WIP

* WIP

* Rolling back config changes

* Fixing make file

* Fixing config for cluster

* WIP

* Fixing system console for clustering

* Fixing default config

* Fixing config

* Fixing system console for clustering

* Tweaking hub setting

* Bumping up time

* merging vendor dir

* Updating vendor dir

* Fixing unit test

* Fixing bad merge

* Remove some testing code

* Moving comment

* PLT-6868 adding db ping retry

* Removing unused loc strings

* Adding defer to cancel

i18n/en.json

@@ -3261,7 +3261,7 @@
   },
   {
     "id": "ent.cluster.config_changed.info",
-    "translation": "Cluster configuration has changed for id=%v.  Attempting to restart cluster service.  To ensure the cluster is configured correctly you should not rely on this restart because we detected a core configuration change."
+    "translation": "Cluster configuration has changed for id={{ .id }}.  The cluster may become unstable and a restart is required.  To ensure the cluster is configured correctly you should perform a rolling restart immediately."
   },
   {
     "id": "ent.cluster.debug_fail.debug",
@@ -3293,7 +3293,7 @@
   },
   {
     "id": "ent.cluster.save_config.error",
-    "translation": "System Console is set to read-only when High Availability is enabled."
+    "translation": "System Console is set to read-only when High Availability is enabled  unless ReadOnlyConfig is disabled in the configuration file."
   },
   {
     "id": "ent.cluster.starting.info",
@@ -4711,14 +4711,6 @@
     "id": "store.sql.open_conn.panic",
     "translation": "Failed to open SQL connection %v"
   },
-  {
-    "id": "store.sql.ping.critical",
-    "translation": "Failed to ping DB err:%v"
-  },
-  {
-    "id": "store.sql.pinging.info",
-    "translation": "Pinging SQL %v database"
-  },
   {
     "id": "store.sql.read_replicas_not_licensed.critical",
     "translation": "More than 1 read replica functionality disabled by current license. Please contact your system administrator about upgrading your enterprise license."