Mark the repo as outdated, add link to new proposal

Author: tschneidereit

Diff for: README.md

@@ -1,27 +1,4 @@
-# Typed Objects Explainer
+# WARNING: Outdated! Typed Objects Explainer
 
-This is an effort to pull together and explain the various typed
-objects spec in an informal fashion. The explanations are divided into
-groups:
-
-- [Core](core.md) defines the core typed objects proposal.
-- [Value types](valuetypes.md) defines an extension to the core
-  proposal to support new kinds of values, akin to numbers and
-  strings.
-- [OO types](ootypes.md) defines an extension to allow
-  typed objects to (more) accurately describe the kinds of
-  things one can describe in Java or C#.
-- [Class syntax](classsyntax.md) explores integration of typed objects
-  with ES6 class syntax and modules.
-- [Operator overloading](overloading.md) describes a mechanism for
-  operator overloading that integrates with the
-  [value types](valuetypes.md) proposal.
-
-**Caveat:** This set of explainers is **very much** a work in
-  progress. The further down that list you go, the less consensus
-  exists on the design.
-
-
-## Interested?
-
-Join the IRC channel at #typed-objects on irc.mozilla.org (irc://irc.mozilla.org/typed-objects).
+This set of explainer documents is for the old, inactive Typed Objects proposal. The new proposal can be found here:
+https://github.com/tschneidereit/proposal-typed-objects