Add a new ansible recipe that can setup a Wendelin site and ensure it's

properly setuped (automatically).
Add tests for this.

/reviewed-on !116

playbook/wendelin-standalone-test.yml

+- name: a play that runs entirely on the ansible host
+  hosts: 127.0.0.1
+  connection: local
+
+  vars:
+    software_release_url: https://lab.nexedi.com/nexedi/slapos/raw/master/software/wendelin/software.cfg
+    bt5_list: erp5_full_text_myisam_catalog erp5_configurator_standard erp5_wendelin_configurator erp5_scalability_test erp5_wendelin_scalability_test erp5_wendelin_auto_configuration
+    startup_playbook_id: wendelin-standalone.yml
+    request_instance_template: request-erp5.j2
+    request_frontend_template: request-erp5-frontend.j2
+    playbook_name: wendelin
+  roles:
+    - standalone-shared
+    - { role: package, package_name: socat, package_state: present }