Fix bug 1470742: Restore clickable contributor links in History tab (#983)
Fix bug 1470742: Restore clickable contributor links in History tab (#983)

We introduced the removed line while fixing bug 1453879. After we fixed
bug 1462419, the line is no longer needed.

Also: Open contributor page in new window to be consistent with
Machinery and Locales tabs.
mathjazz/pontoon,mathjazz/pontoon,mathjazz/pontoon,jotes/pontoon,mozilla/pontoon,mozilla/pontoon,mozilla/pontoon,mozilla/pontoon,mathjazz/pontoon,jotes/pontoon,mozilla/pontoon,jotes/pontoon,mathjazz/pontoon,jotes/pontoon