Fixes bug 1094573 - Added a link to report/list/ to the signature report page.

@peterbe r?

![signature-report-link](https://cloud.githubusercontent.com/assets/328790/4931005/9e9441d0-656f-11e4-8343-2d709dcbaf8c.png)

That URL looks odd. Perhaps better to call it "See the equivalent Report list page"