Merge pull request #50 from WebAssembly/readme

Update readme to link to the two active stack-switching proposals

Author: slindley

README.md

@@ -1,3 +1,49 @@
+# Stack-Switching Proposal for WebAssembly
+
+This repository is a clone of
+[`WebAssembly/spec`](https://github.com/WebAssembly/spec/). It is meant for
+discussion, prototype specification, and implementation of a proposal to add
+support for stack-switching.
+
+There are currently two active stack-switching proposals: Typed Continuations
+(aka WasmFX) and Bag of Stacks. Documentation about each proposal is available
+in separate directories of the `main` branch of this repository (as detailed
+below).
+
+In order to minimise future difficulties merging upstream, the two
+corresponding extensions to the reference interpreter will be
+maintained in separate branches (as detailed below).
+
+## Typed Continuations Proposal
+
+* See the [explainer](proposals/continuations/Explainer.md) for a high-level
+  summary of the proposal.
+
+* See the [overview](proposals/continuations/Overview.md) for a more formal
+  description of the proposal.
+
+* See the [examples](proposals/continuations/examples) for Wasm code for
+  implementing various different features including lightweight threads, actors,
+  and async/await.
+
+* An
+[implementation](https://github.com/WebAssembly/stack-switching/tree/wasmfx) is
+available as an extension to the reference interpreter. It is accesible from the
+`wasmfx` branch.
+
+## Bag of Stacks Proposal
+
+* See the [explainer](proposals/bag-o-stacks/Explainer.md) for a high-level
+  summary of the proposal.
+
+* An extension to the reference interpreter will be made available in the
+`bag-o-stacks` branch in due course.
+
+
+Original README from upstream repository follows.
+
+--------------------------------------------------------------------------------
+
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