Anything older than 9.3 is unsupported by Postgres: https://www.postgresql.org/support/versioning/.
I don't think we should claim support in our module for unsupported versions,
particularly if we don't have CI on them.
Since we're *only* running CI on 9.2 at the moment, that's the safe claim
for our module support, even though it's already unsupported by Postgres.
See https://docs.travis-ci.com/user/database-setup/#using-a-different-postgresql-version
I'll raise a separate ticket about testing and supporting newer versions,
it's out of scope for this PR.
Steve Boyd
Robbie Averill
Ingo Schommer
Dylan Wagstaff
Damian Mooyman
Ingo Schommer
Sean Harvey
Will Rossiter