requester.js cannot shutdown while monitor.js is running

[gerberasa]

If we run requester.js without monitor.js, we can shutdown requester without problem.
But when monitor.js is running, we cannot shutdown the requester.js (always shown "SIGINT signal received" line after line). Run on Windows7.

NB: same issue with monitoring-tool.js

`
//requester.js

const cote = require('cote')
const requester = new cote.Requester({name: 'currency conversion requester' , namespace : 'rnd' })

//build request array
const request = { type: 'randomRequest' , from : 'usd' , to : 'eur' , amount : 100 }

requester.send(request, (res) => {
console.log('Sent request: ' + request)
console.log('Received response: ' + res)
})

//graceful shutdown
process.on('SIGINT', function(){
console.log('SIGINT signal received')
requester.close(function(){process.exit(0)})})

//graceful shutdown
process.on('SIGTERM', function(){
console.log('SIGTERM signal received')
requester.close(function(){process.exit(0)})})
`