Precise Memory.grow semantics in doc page

[juj]

1. Clicking on link Memory.grow in https://github.com/WebAssembly/design/blob/master/JS.md#webassemblymemoryprototypegrow in Perform Memory.grow with delta d. sentence points to https://github.com/WebAssembly/spec/blob/master/interpreter/spec/memory.mli#L27 which gives a 404.

2. Does Perform Memory.grow with delta d. there mean with delta d pages, or with delta d bytes?

Presumably Memory.grow() behaves identical to the grow_memory opcode at https://github.com/WebAssembly/design/blob/e2be77eaac770268a4c22fb09c6f648de7b9b6b8/Semantics.md#resizing, so this would be in pages?

[littledan]

We should take down the JS.md page. It is now subsumed by this document: https://webassembly.github.io/spec/js-api/index.html

[jfbastien]

We should replace it instead, with forwarding links, and host the editor's draft on webassembly.org. This probably fits in the webassembly.org maintenance discussion.