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/clusterdevel/roles/minishift/templates/hostdev.yml.j2

@@ -64,7 +64,7 @@ spec:
         - name: awx-memcached
           image: memcached
         - name: postgres
-          image: postgres:9.6
+          image: postgres:10
       volumes:
         - name: localdev
           persistentVolumeClaim: