Fixed Pentadactyl with vertical tabs.

Fixed Pentadactyl with vertical tabs.

Way back in commit c245702041670b927f11bb7bf61d99f2fdc9e6e7 Pentadactly
broke vertical tabs, such as those in Tab Kit 2nd edition, by explicitly
adding CSS to set the maximum height for the tab bar:

    [dactyl-australis=true] .tabbrowser-tabs {
        min-height: 0 !important;
        max-height: 24px !important;
    }

Rather than recompile Pentadactyl each time we can fix that with a line
of custom CSS in .pentadactylrc.