Make API key combination of secret and service ID

In research we’ve seen people mix up the service ID and API key because
they’re both 36 character UUIDs. We can’t get rid of the service ID
because it’s used to look up the API key.

Instead, we should change API key to be one long string, which contains
both the service ID, API key and (optionally) the name of the key. For
example:

```
casework_production-8b3aa916-ec82-434e-b0c5-d5d9b371d6a3-dcdc5083-2fee-4fba-8afd-51f3f4bcb7b0
```

We still need to keep the old, separate, key and service ID for a while
until people have updated their clients. But they’re now both on this
page, rather than on two separate pages, which should make for less
fussing anyway.

This shouldn’t be rolled out until the new clients are available.

- [ ] https://github.com/alphagov/notifications-python-client/pull/36
- [ ] https://github.com/alphagov/notifications-node-client/pull/10
- [ ] https://github.com/alphagov/notifications-ruby-client/pull/15
- [ ] https://github.com/alphagov/notifications-java-client/pull/38
- [ ] PHP????

app/main/views/api_keys.py

@@ -3,7 +3,7 @@ from flask_login import login_required
 from app.main import main
 from app.main.forms import CreateKeyForm, Whitelist
 from app import api_key_api_client, service_api_client, notification_api_client, current_service
-from app.utils import user_has_permissions
+from app.utils import user_has_permissions, email_safe
 from app.notify_client.api_key_api_client import KEY_TYPE_NORMAL, KEY_TYPE_TEST, KEY_TYPE_TEAM
 
 
@@ -80,8 +80,12 @@ def create_api_key(service_id):
             key_name=form.key_name.data,
             key_type=form.key_type.data
         )
-        return render_template('views/api/keys/show.html', secret=secret,
-                               key_name=form.key_name.data)
+        return render_template(
+            'views/api/keys/show.html',
+            secret=secret,
+            service_id=service_id,
+            key_name=email_safe(form.key_name.data, whitespace='_')
+        )
     return render_template(
         'views/api/keys/create.html',
         form=form