Add hint about replication slots when nearing wraparound

When Who What
2017-12-29 14:10:08 Simon Riggs (simon) Closed in commitfest 2018-01 with status: Committed
2017-12-29 14:09:57 Simon Riggs (simon) Added simon as committer
2017-12-27 11:39:43 Michael Paquier (michael-kun) New status: Ready for Committer
2017-12-27 07:48:43 Feike Steenbergen (feike) Changed authors to Feike Steenbergen (feike)
2017-12-27 07:48:25 Feike Steenbergen (feike) Attached mail thread CAK_s-G20K55okEo53Y3BDpuDcGbAYjMXcwzsVR1+DRMB-S25TA@mail.gmail.com
2017-12-27 07:48:24 Feike Steenbergen (feike) Created patch record