update header to provide alt tags for images and remove explicit svg fallback path, which will allow static_pages.js to simply search for a fallback png with a name identical to svg
update header to provide alt tags for images and remove explicit svg fallback path, which will allow static_pages.js to simply search for a fallback png with a name identical to svg

YaleDHLab/voices,YaleDHLab/voices,YaleDHLab/voices,YaleDHLab/voices