Update the service name validation in the ServiceNameForm and AddServiceForm to check the email_safe version

of the name against a list of all service email_from fields.
Update find_all_service_names to find_all_service_email_from, which returns the email_from of all services.

tests/app/test_utils.py

@@ -0,0 +1,8 @@
+from app.utils import email_safe
+
+
+def test_email_safe_return_dot_separated_email_domain():
+    test_name = 'SOME service  with+stuff+ b123'
+    expected = 'some.service.withstuff.b123'
+    actual = email_safe(test_name)
+    assert actual == expected