Update github pages demo for go 1.12+
Update github pages demo for go 1.12+

- go 1.12 optimizes memory allocation for wasm - see
  https://github.com/golang/go/issues/27462. This was causing the demo to OOM
  on memory restricted devices (e.g. phones).
- js namespace changed so we need to adapt to that

niklasfasching/go-org,niklasfasching/go-org