Add a custom, so I can translate "Day" "Week" "Month" "Today" and other string

[tumashu]

(defun cfw:render-toolbar (width current-view prev-cmd next-cmd)
  "[internal] Return a text of the toolbar.
WIDTH is width of the toolbar.
CURRENT-VIEW is a symbol of the current view type. This symbol is used to select the button faces on the toolbar.
PREV-CMD and NEXT-CMD are the moving view command, such as `cfw:navi-previous(next)-month-command' and `cfw:navi-previous(next)-week-command'."
  (let* ((prev (cfw:render-button " < " prev-cmd))
         (today (cfw:render-button "Today" 'cfw:navi-goto-today-command))
         (next (cfw:render-button " > " next-cmd))
         (month (cfw:render-button
                 "Month" 'cfw:change-view-month
                 (eq current-view 'month)))
         (tweek (cfw:render-button
                 "Two Weeks" 'cfw:change-view-two-weeks
                 (eq current-view 'two-weeks)))
         (week (cfw:render-button
                "Week" 'cfw:change-view-week
                (eq current-view 'week)))
         (day (cfw:render-button
               "Day" 'cfw:change-view-day
               (eq current-view 'day)))
         (sp  " ")
         (toolbar-text
          (cfw:render-add-right
           width (concat sp prev sp next sp today sp)
           (concat day sp week sp tweek sp month sp))))
    (cfw:render-default-content-face toolbar-text 'cfw:face-toolbar)))