Originally motivated by fixing #263 (add a mod list), the root cause
of which was that we had a number of orphaned pages, one being the
admins list.
In the upstream, we moved links to a number of infrequently-accessed
pages to a secondary nav in the sidebar. This commit implements a
similar approach to provide links to the admin list and modlog. To
make the nav less visually unbalanced, Random Post/User were also
moved out of the header.
To provide mobile support, this secondary nav is presented in the
hamburger menu. This also provides a place to link /rules, which
otherwise has no link on mobile (that I can readily find).
Finally, the original intent of providing a mod list motivates some
style changes to admins.html to get rid of visible truescore, make
names appear consistently with names elsewhere, and ensure links to
leaderboard aren't accidentally leaked.
