External IP/IPs for Mongo DB high availability

[Mongo DB high availability](https://github.com/Azure/azure-quickstart-templates/tree/master/mongodb-high-availability)

Thanks for your awesome job!
I've successfully deployed a cluster of Medium size and now I want to use it outside of Azure. Could you give me a clue on what's the best way to make it accessible from outside using external IP/IPs?

I want to give developers access to some databases from their workplaces, with no need for jump-boxes, just like that: `mongodb://u:p@server1.blah-blah.cloud,u:p@server2.blah-blah.cloud,u:p@server3.blah-blah.cloud`

This is how everything looks like right now:

The relevant entry point is the linked mongodb-high-availability template; read its deployment parameters and current network exposure first. Define whether external developer access is in scope and what secure, supported endpoint configuration would count as done; the issue provides no test or implementation file.

Written by the indexing model from the issue text.