Upgrade to postgres 10.6

- use awx-python in shebang in dev env
  - scl enable where needed for rhel7 & container installs
  - use scram-sha-256 pg user hashing by default
  - ensure psycopg2 is using the correct PG_CONFIG at build time for the right libpq version

tools/docker-compose-cluster.yml

@@ -90,8 +90,13 @@ services:
       - CLUSTERED=true
       - CLUSTER_WITH=rabbitmq_1
   postgres:
-    image: postgres:10.7
+    image: centos/postgresql-10-centos7
     container_name: tools_postgres_1
+    environment:
+      POSTGRESQL_USER: awx
+      POSTGRESQL_PASSWORD: awxpass
+      POSTGRESQL_DATABASE: awx
+      POSTGRESQL_ADMIN_PASSWORD: postgrespass
   memcached:
     image: memcached:alpine
     container_name: tools_memcached_1