Folding StrictWhitespace into the Strict ruleset of RFC7230, per dev@ poll.

This choice is unanimous, although StrictURI (a different RFC) still hasn't
found absolute concensus.

An ap_mmn bump will follow (major, this removes a struct elt)



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1758226 13f79535-47bb-0310-9956-ffa450edef68