Banner headings updated throughout the Archive

I have updated the headings in the gray banner throughout the Archive. The purpose of these changes was to make the banner consistent across the site. At any page of the Archive, the banner now always shows the main section heading (e.g., Published Works, In Whitman's Hand, etc.) and, when appropriate, the main sub-heading (e.g., within Published Works, either Books or Periodicals).

~Janel