Add node js snippets to generate hmac token

[madhavanramachandran]

Node js snippets to generate hmac token from cli.

[shubhu251]

@madhavanramachandran please add apiKeyId in the file
authentication/hmac_node_js/index.js

const apiKeyId = argv['apiKeyId']

reference https://github.com/cybrilla/fp-snippets/blob/master/authentication/hmac-postman-pre-request-script.js

[shubhu251]

file : authentication/hmac_node_js/index.js link no 28 add replace tenant with apiKeyId

const httpHeaders = { 
    'content-type': 'application/json',
    'Authorization': apiKeyId +":"+hmacToken,
    'MFProDate': requesttime,
    'x-tenant-id': tenant
}

[shubhu251]

remove default domain from here file authentication/hmac_node_js/index.js line no 12
const hostName = argv['domain'] || 'https://api.fintechprimitives.com'