Review anchor styling site wide
Throughout the site we have a number of different styles for links. We need to review them and set some rules for when to use which styling in order to keep consistency.
We also need to look into consolidating the style for the hover/focus/active state. See https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/4576
The above MR needs a guideon how (in terms of design) and when apply a style for each state.