nl_tokens: Utility to promisify a Node function
pl_tokens: function nodeCall ( nodeFunc /* args... */ ) { var nodeArgs = <mask> . prototype . slice . call ( arguments , 1 ) ; return new Promise ( function ( resolve , reject ) { /**
       * Resolve a node callback
       */ function nodeResolver ( err , value ) { if ( err ) { reject ( err ) ; } else { resolve ( value ) ; } } nodeArgs . push ( nodeResolver ) ; nodeFunc . apply ( nodeFunc , nodeArgs ) ; } ) ; }