Remove Space Odyssey copy from error pages

While funny, some people who report bugs appear not to get the
reference, which might lead them to feel insulted. Quoting the
description of the Bugzilla keyword "ux-tone" used by the user
experience team:

    User experience principle: interfaces should not blame the user, or
    communicate in a way that is overly negative or dramatic.

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I also intentionally remove the bug link. My thinking is that the error message is helpful enough already, suggesting specific courses of action, that linking to a bug form seems unprofessional (at least to me), and that truly important bugs will be reported whether we provide a link or not. But I am open to different opinions on this part of the PR.