Bug#892750: Client version for current PostgreSQL version

[Arjen Balfoort]

I've posted this issue on the xTuple forum as well and when I asked 
which client version works with PostgreSQL 9.7.6 and higher, this was 
the answer:
"4.11.0 and higher work without complaint on PostgreSQL 9.3 - 9.6. We 
have not vetted PG 10 yet."

xTuple forum topic: 
https://forums.xtuple.com/t/postgresql-version-too-new-for-xtuple-client-in-debian-stretch/