Only show nhs radios if user has nhs domain email

Also split local NHS into two groups following designer advice
on readability.

app/main/forms.py

@@ -249,7 +249,8 @@ def organisation_type(label='Who runs this service?'):
             ('central', 'Central government'),
             ('local', 'Local government'),
             ('nhs_central', 'NHS – central government agency or public body'),
-            ('nhs_local', 'NHS Trust, GP surgery or Clinical Commissioning Group'),
+            ('nhs_local', 'NHS Trust or Clinical Commissioning Group'),
+            ('nhs_local', 'GP practice'),
             ('emergency_service', 'Emergency service'),
             ('school_or_college', 'School or college'),
             ('other', 'Other'),
@@ -258,6 +259,18 @@ def organisation_type(label='Who runs this service?'):
     )
 
 
+def nhs_organisation_type(label='Who runs this service?'):
+    return RadioField(
+        label,
+        choices=[
+            ('nhs_central', 'NHS – central government agency or public body'),
+            ('nhs_local', 'NHS Trust or Clinical Commissioning Group'),
+            ('nhs_local', 'GP practice'),
+        ],
+        validators=[DataRequired()],
+    )
+
+
 class FieldWithNoneOption():
 
     # This is a special value that is specific to our forms. This is
@@ -588,13 +601,17 @@ class OrganisationDomainsForm(StripWhitespaceForm):
 
 class CreateServiceForm(StripWhitespaceForm):
     name = StringField(
-        u'What’s your service called?',
+        "What’s your service called?",
         validators=[
             DataRequired(message='Can’t be empty')
         ])
     organisation_type = organisation_type()
 
 
+class CreateNhsServiceForm(CreateServiceForm):
+    organisation_type = nhs_organisation_type()
+
+
 class NewOrganisationForm(
     RenameOrganisationForm,
     OrganisationOrganisationTypeForm,