Review if the reason for disallowing the start function still exists

[axic]

Disallowing the start function and using a main function was decided based on a limitation in the Wasm Javascript API.

I think it is time to review this limitation and if it still holds.

[jakelang]

@axic what is the status of this?

[axic]

Somebody needs to review it? 😉

[pepyakin]

regarding this:

In the WebAssembly Javascript API however the start function is executed right during instantiation, which leaves no time for the client to acquire the memory area.

this still holds as far as I know.