Fixed stashing of query string for when authentication failed.

A bug had been introduced which meant that even though we saved the
query string into local storage, we then overwrote it with an empty
query string before reading the saved value back when the page was
loaded again following the authentication succeeded.
Add basic favicon implementation and moved delete button to right.

Delete button moved to the far right side of the list, leaving space
for a favicon on the left.  Current favicon implementation is poor in
that it tries to access the favicon from the toplevel of each site
rather than trying to inspect the contents of any link elements in the
referenced document.  This will be investigated in future work.
Page layout improved by using a Bootstrap linkified list.