Let NHS Trusts and CCGs choose own organisation

All we do via support is ask which organisation they work for and
manually assign their service to it. This commit makes that process self
service.

We think we have all the trusts and clinical commissioning groups
loaded into the database now.

This will make the go live process smoother for these teams.

app/models/service.py

@@ -595,7 +595,7 @@ class Service(JSONModel):
     def able_to_accept_agreement(self):
         return (
             self.organisation.agreement_signed is not None
-            or self.organisation_type == 'nhs_gp'
+            or self.organisation_type in {'nhs_gp', 'nhs_local'}
         )
 
     @property