message: Allow `type` fields in metafiles to hide type prompt
  This closes
diff: @@ -40,11 +40,21 @@ async function readMetaData(
  }
  }
  + // We can remove this once the prompt for choosing `--npm` or `--docker` is gone
  + if (pkg && pkg.now && pkg.now.type) {
  + type = nowConfig.type
  + }
  +
  + // The same goes for this
  + if (nowConfig && nowConfig.type) {
  + type = nowConfig.type
  + }
  +
  if (!type) {
  type = await determineType(path)
  // Both `package.json` and `Dockerfile` exist! Prompt the user to pick one.
  - // We can remove this soon (details are internal)
  + // We can remove this soon (details are internal) - also read the comment paragraph above
  if (type === 'docker' && (pkg && dockerfile)) {
  const err = new Error(
  'Ambiguous deployment (`package.json` and `Dockerfile` found). ' +
  