Restore README and proposal dir from main-legacy (#241)

Author: tlively

README.md

@@ -1,5 +1,17 @@
-[![CI for specs](https://github.com/WebAssembly/spec/actions/workflows/ci-spec.yml/badge.svg)](https://github.com/WebAssembly/spec/actions/workflows/ci-spec.yml)
-[![CI for interpreter & tests](https://github.com/WebAssembly/spec/actions/workflows/ci-interpreter.yml/badge.svg)](https://github.com/WebAssembly/spec/actions/workflows/ci-interpreter.yml)
+[![Build Status](https://travis-ci.org/WebAssembly/threads.svg?branch=master)](https://travis-ci.org/WebAssembly/threads)
+
+# Threads Proposal for WebAssembly
+
+This repository is a clone of github.com/WebAssembly/spec/. It is meant for
+discussion, prototype specification and implementation of a proposal to threads
+support to WebAssembly.
+
+See the [overview](proposals/threads/Overview.md) for a summary of the proposal.
+
+A formatted version of the spec with proposed changes is available here:
+[webassembly.github.io/threads](https://webassembly.github.io/threads/).
+
+Original README from upstream repository follows...
 
 # spec
 

proposals/threads/ConditionalSegmentInitialization.md

@@ -0,0 +1,4 @@
+# Proposal to conditionally initialize segments
+
+This has been separated into
+[its own proposal](https://github.com/WebAssembly/conditional-segment-initialization/).

proposals/threads/Globals.md

@@ -0,0 +1,5 @@
+
+# Import/Export mutable globals proposal
+
+This has been separated into
+[its own proposal](https://github.com/WebAssembly/mutable-global/).