reuse solution Buffer at low level API, decode into array at high level API

[derhuerst]

With the split into a high-level and a low-level interface I will PR soon on master, it would make sense to decode the solution into an object that looks like this:

{
  A: true,
  B: false,
  C: true
}

We should also let the low-level interface write into a Buffer instead of returning an array.