Revise the versions on a few queries, improve query tests

* Add ability to specify the sslmode parameter when connecting to
  PostgreSQL

* Fix min versions for replication queries

* Add query-tests target to main Makefile

tests/docker-compose.yml

@@ -23,7 +23,7 @@ services:
       test: [ "CMD-SHELL", "pg_controldata /var/lib/postgresql/data/ | grep -q 'in production'" ]
       interval: 5s
       timeout: 2s
-      retries: 10
+      retries: 20
     command: >
       postgres -c ssl=on
                -c ssl_cert_file='/etc/ssl/certs/ssl-cert-snakeoil.pem'

tests/test-config.yml

@@ -8,8 +8,9 @@ dbhost: db
 dbport: 5432
 dbuser: postgres
 
-# Allow some insecure SSL parameters for the 9.2 test
-ssl_ciphers: DEFAULT@SECLEVEL=1
+# The SSL cipher parameters are too old in the 9.2 container, so we allow the tests
+# to be run without encryption
+ssl_mode: prefer
 
 # Pull in the standard metrics
 include: