Can new lines be automatically for templates that are overridden with marathon app labels?

[willgorman]

Missing line terminating characters at the end of a template provided via application labels seems to be an easy way to cause invalid config to be generated (#423, #147). Looking at all the default templates in https://github.com/mesosphere/marathon-lb/blob/master/Longhelp.md it's not immediately obvious that overriding them requires adding a new line. Would it be helpful to have marathon-lb ensure that the new line is added to those automatically?