use YAML for celery serialization

- add CELERY_ACCEPT_CONTENT, CELERY_TASK_SERIALIZER and
  CELERY_RESULT_SERIALIZER in gnuviechadmin.settings.base
- add pyaml to requirements/base.txt

gnuviechadmin/gnuviechadmin/settings/base.py

@@ -287,6 +287,9 @@ CELERY_TASK_RESULT_EXPIRES = None
 CELERY_ROUTES = (
     'osusers.tasks.LdapRouter',
 )
+CELERY_ACCEPT_CONTENT = ['yaml']
+CELERY_TASK_SERIALIZER = 'yaml'
+CELERY_RESULT_SERIALIZER = 'yaml'
 ########## END CELERY CONFIGURATION
 
 

requirements/base.txt

@@ -10,3 +10,4 @@ celery==3.1.11
 billiard==3.3.0.17
 kombu==3.0.16
 pytz==2014.3
+pyaml==14.05.7