inputrc: add F6 shortcut that's similar to F5
web.py: add `pyer` field to Response

Indicates whether or not the response was gotten from a python exception
(HTTPError), which I consider to be a perfectly valid response from a
web server, and definitely not exception worthy. But it's sometimes
useful to know if the return code was an error, and python has already
done the work for us (that is, enumerating which codes indicate errors)