[IMP] auth_oauth: set default 'zocial' css_class

The buttons for new providers needs at least the zocial css class to be seen as button. As the field css_class is not in the default form view, add it by default.

addons/auth_oauth/auth_oauth.py

@@ -21,4 +21,5 @@ class auth_oauth_provider(osv.osv):
     }
     _defaults = {
         'enabled' : False,
+        'css_class' : "zocial",
     }