[idn] Using the last DNS header bit

[Olafur Gudmundsson <ogud@tislabs.com>]

There are number of proposals in this working group suggesting to
use this bit for expressing support for IDN. There will be deployment
problems using this bit due to some old DNS software using this bit
for non standardized behavior. This bit is being reserved for future
use, in case we encounter a problem that is of extremely high importance 
and where there is no way around it.

Most of the proposals that I have read can just as well use one of
the EDNS extension functions, for instance the extended flags (there are 12 
1-bit flags available).
Authors of IDN proposals should feel free to propose multiple
bits or EDNS options if that makes sense.

	Olafur (WG chair of DNSEXT). -