wording change

[Erik Ostrom <eostrom@research.att.com>]

on an unrelated side note, i would change this sentence:

>As such, compliant implementations are encouraged to support the
>mcp-cord package.

to refer to "MCP 2.1 implementations" rather than "compliant
implementations".  although the sentence is correct as it stands, the
use of "compliant" here has the connotation that to comply you should
support cords.  its use earlier in the paragraph seems right, though.
although i might get rid of the part where we say "cords are not part
of mcp 2.1", since that really begs the question "why are they in the
spec then" (to which the answer is "let's not argue about any more
things than we have to at this point").

--erik