* Olm no longer supports setting the stack/memory size at runtime,
   so don't (they're now set to be that in the Olm build).
 * Copy the wasm file from the Olm library (see multiple comments
   about it being in the wrong place and webpack being awful).

Now that Olm needs to be inited asynchronously anyway, we can just
pass the options to Olm.init(), and as long as we do that before we
start the js-sdk, we're all good.

This will means the olm js is now part of the main bundle but since
it's now just a wrapper around the wasm, this is probably faster.

Also add the directwatch flag to olm.wasm because otherwise it
doesn't seem to copy the file in watch mode...