puppet: Add config variables for Postgres master streaming replication

(imported from commit 6ffdb08c335452c60223c3129cf13c70a6ef439f)

servers/puppet/modules/humbug/files/postgresql/postgresql.conf

@@ -577,3 +577,9 @@ log_rotation_size = 100MB
 log_min_duration_statement = 500
 log_line_prefix = '%m [%c]: [%l-1] '
 log_lock_waits = on
+
+wal_level = hot_standby
+archive_mode = on
+archive_command = 'cp -f %p /var/lib/postgresql/9.1/main/data/archive/%f </dev/null'
+
+# Temporary settings