auth_param basic&digest utf8 on|of

auth_param basic&digest utf8 on|of

new utf8 auth_param option to enable UTF-8 translation of the requests
sent to auth helpers. HTTP uses iso-8859-1 in authentication credentials,
but many authentication backends expects UTF-8 as charset.

Note: This does NOT solve the bigger HTTP problem of authentication using
characters outside iso-8859-1, only simlplifies things a bit by allowing
helpers to operate in UTF-8 even when HTTP operates in iso-8859-1.

An alternative would be to add the translation to each helper.