Passphrase for in-proc deamon

[richardschneider]

The new --pass ... option should be set for the in-proc deamon. For example

const df = DaemonFactory.create({ type: 'proc', exec: IPFS })
const options = {
  args: ['--pass ipfs-is-awesome-software']
}
df.spawn(options, (err, _ipfsd) => ...)

Needed by ipfs/js-ipfs#1133

[daviddias]

fixed with #187