remove browsableitem

it was only used by the choose service page, and then only in kludgy
ways (eg: creating a list containing one item called "add service"),
so lets rip it out and make this page bespoke. Especially now that it's
changed so much.

app/notify_client/service_api_client.py

@@ -1,9 +1,6 @@
 from __future__ import unicode_literals
 
-from flask import url_for
-
 from app.notify_client import NotifyAdminAPIClient, _attach_current_user
-from app.utils import BrowsableItem
 
 
 class ServiceAPIClient(NotifyAdminAPIClient):
@@ -426,21 +423,3 @@ class ServiceAPIClient(NotifyAdminAPIClient):
             "updated_by_id": user_id
         }
         return self.post("/service/{}/delivery-receipt-api".format(service_id), data)
-
-
-class ServicesBrowsableItem(BrowsableItem):
-    @property
-    def title(self):
-        return self._item['name']
-
-    @property
-    def link(self):
-        return url_for('main.service_dashboard', service_id=self._item['id'])
-
-    @property
-    def destructive(self):
-        return False
-
-    @property
-    def hint(self):
-        return None