local-port 
Find open or closed local port within a range
Usage
require('local-port').findOpen(3001, function(err, port) {
if(err)
console.error(err);
console.log(port)
})
API
findOpen(start, [end,] callback)=>callback(err, port)findClose(start, [end,] callback)=>callback(err, port)isPortTaken(port, callback)=>callback(err, taken)