Fixes Win32 cgi 500 errors when QUERY_ARGS or other strings include

  Fixes Win32 cgi 500 errors when QUERY_ARGS or other strings include
  extended characters (non US-ASCII) in non-utf8 format.  This brings
  Win32 back into CGI/1.1 compliance, and leaves charset decoding up
  to the cgi application itself.

  Accomplished this by utf-8 encoding of plain octets for user and header
  data, so that the apr_proc_create() translates back to single unicode
  characters.  This won't necessarily translate into the correct octet
  depending on the codepage used by the cgi app.  That's the next task.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@95865 13f79535-47bb-0310-9956-ffa450edef68