Merge pull request #16171 from chrisarcand/fail-unless-pg-95

Add PostgreSQL version restriction

config/initializers/postgres_required_versions.rb

@@ -0,0 +1,8 @@
+ActiveRecord::ConnectionAdapters::PostgreSQLAdapter.prepend Module.new {
+  def initialize(*args)
+    super
+    if postgresql_version < 90400 || postgresql_version >= 90600
+      raise "The version of PostgreSQL being connected to is incompatible with #{I18n.t("product.name")}"
+    end
+  end
+}