* liquidator: forcefully exit process if snapshot job die
* client: return snapshot_job join handle so it can be watched for early unexpected exit
(cherry picked from commit 2520c7d095)
* service-mango-health: add a new service that compute health for all mango accounts and persist an history in postgres sql
(cherry picked from commit 6aa8a883f4)
Serge Farny
Christian Kamm