Add reference to hyperterm, Remove HTML escaping from Highlight.js

Highlight.js does a strange thing of escaping HTML. Why. Anyway, this
was fixed by removing the escape line:

    -return e.replace(/[&<>]/gm,function(e){return I[e]})
    +return e

js/pgsh.js

@@ -77,7 +77,9 @@ function pgsh(ev) {
           '# Parsley Gardens Website\n\n' +
           '1. Made by Weiyi Lou ' + new Date().getFullYear() + '\n' +
           '2. Done for fun.\n' +
-          '3. Not a real terminal.',
+          '3. Not a real terminal.\n' +
+          '4. But <a target="_blank" href="https://hyperterm.org/">this</a>' +
+            ' totally is.'
       }
     },
     'mnt': {},