Improve styling of builder links in sheriff-o-matic.

-Put each link on it's own line.
-Make them look like normal links.
No special font-size and leave the underline.

TBR=leviw@chromium.org

Review URL: https://codereview.chromium.org/486203007

git-svn-id: svn://svn.chromium.org/blink/trunk@180626 bbb929c8-8fbe-4397-9dbb-9b2b20218538