[BitBucket user: Alain Mazy]
[BitBucket date: 2017-12-05.13:58:58]

Based on this topic: https://groups.google.com/d/msg/orthanc-users/8SrGfjiL6E0/iULUOkz5AgAJ

When a PG server is restarted, Orthanc PG connection object is not valid anymore and Orthanc must be restarted in order to create a new PG connection.

In case of 'connection' issue, the PG connection object shall try to reconnect.  That would be helpful to make the connection resilient to other transient errors as well.