Error pages should report the error code to the user

[Māris Fogels]

When viewing a 404 or 500 error page the user does not see the actual error code. This makes it difficult for technical users (engineers) to tell what the cause of the page error to be.

Steps to reproduce:

1. Visit a made-up url: http://try.cloud.ubuntu.com/foo/run

What happens: you see a page that says 'Oops!'
What should happen: you see a page that says, at minimum, '404', and some text about the page being Not Found

[Michael Hall (mhall119)]

The 404 pages actually do specify that it was a 404, it's just that the example given tries to run an instance on a campaign called "foo", and when that lookup fails it raises a 500 error. If you go to http://try.cloud.ubuntu.com/foo/bar/ you will see the 404 message.