Move service history into it own file

We’re going to do some work on this page, let’s put it in a sensible
place first before we add a bunch more code to the wrong place.

app/main/__init__.py

@@ -15,6 +15,7 @@ from app.main.views import (  # noqa isort:skip
     find_services,
     find_users,
     forgot_password,
+    history,
     inbound_number,
     index,
     invites,