Add detailed request failure information to the web UI

[bobobo1618]

At the moment, the only data displayed for failed requests are the number of failures on a URL and the number of each type of failure globally.

E.g. if /api/getitem has 3 404 errors and 2 503 errors, the /api/getitem URL shows 5 failures and the global failures show 3 404s and 2 503s.

If /api/getcheese has 2 404 errors and 10 503 errors, it will show 12 failures for that URL and the global counters will show 5 404s and 12 503s.

The problem is that with the only available data being 5 failures on the first endpoint, 12 failures on the second, 5 global 404s and 12 global 503s, it is impossible to tell which endpoints received which failures. /api/getitem could have had all the 404s and /api/getcheese could have had all the 504s for all we know given the data at the end.

I know that this can be logged manually using the events API but it would be nice if this was displayed in the web UI. E.g. by clicking a URL with faliures in the main view, you can get a breakdown of failure types. By navigating to the failures page and clicking a failure type, you can get a breakdown of the URLs.

[Jahaja]

Agree. I've added method and name columns on the failures tab. See 08796d9.