Integrate with Xero#4

It would be great if the billing system integrated with Xero. This would be useful for service providers (MSPs) who have Xero as their current accounting system.

We have started working on this feature. I will post on this more tomorrow.

This weeks progress:

• We have basic Auth and data sharing working.
• System automatically maps clients to Xero customers when the name matches.
• The system allows clients to match a client from available list of clients.
  – When an invoice is approved, the system creates invoice in Xero.

This feature is released!