Add section to DHF documentation on configuring DHF app servers to require SSL

[danielholgate]

Documentation enhancement request. Please add a section to the documentation page ( https://marklogic.github.io/marklogic-data-hub ) titled "Securing REST end points" or similar, with instructions on what needs to be done in a DHF project to make endpoints use HTTPS. Also point from here to the example ssh project for an example https://github.com/marklogic/marklogic-data-hub/tree/master/examples/ssl (it's great we have the example project, but developers need to go searching for it and it's not obvious from the main page. adding a section to our main documentation makes it clear production-ready secured systems are a priority)

[ryanjdew]

Thank you for filing an issue. An internal JIRA ticket has been filed: https://project.marklogic.com/jira/browse/DHFPROD-1968