Emit HTML non-200 status reports. Such requests are always sent as UTF-8 
documents.
Status can be one of the following:
- authorise(Method)
 - Challenge authorization. Method is one of
basic(Realm) 
digest(Digest) 
 
- authorise(basic, Realm)
 - Same as 
authorise(basic(Realm)). Deprecated. 
- bad_request(ErrorTerm)
 
- busy
 
- created(Location)
 
- forbidden(Url)
 
- moved(To)
 
- moved_temporary(To)
 
- no_content
 
- not_acceptable(WhyHtml)
 
- not_found(Path)
 
- method_not_allowed(Method, Path)
 
- not_modified
 
- resource_error(ErrorTerm)
 
- see_other(To)
 
- switching_protocols(Goal, Options)
 
- server_error(ErrorTerm)
 
- unavailable(WhyHtml)