Invitation is not sent when server is behind proxy

[boriska70]

Not relevant for Cloud/CI but happens in local office network.
express-mailer should get a proxy settings, if relevant.
See:

• server/node_modules/express-mailer/lib/express-mailer.js - code that eventually should use the proxy as one of the options
• nodemailer - nodejs infrastructure used by express-mailer (full example - https://github.com/nodemailer/nodemailer/blob/v2.3/examples/proxy/http-proxy.js). NOTE that we currently use v.0.7.1 - should check if it supports proxy or should be updated
• server/routes/accounts.js (const sendInvitation) - here we should pass the proxy details

[boriska70]

The problem is that express-mailer uses nodemailer v.0.7.1 but proxy support was introduced in nodemailer 2.2.0