User cache for service in send_to_provider methods.

This will remove a call to the db if the service exists in the cache.

app/serialised_models.py

@@ -75,6 +75,7 @@ class SerialisedTemplate(SerialisedModel):
 class SerialisedService(SerialisedModel):
     ALLOWED_PROPERTIES = {
         'id',
+        'name',
         'active',
         'contact_link',
         'email_from',
@@ -83,6 +84,8 @@ class SerialisedService(SerialisedModel):
         'rate_limit',
         'research_mode',
         'restricted',
+        'prefix_sms',
+        'email_branding'
     }
 
     @classmethod