Covert "\n " to "br" so that newlines are displayed correctly to users.

See https://www.pivotaltracker.com/story/show/82069672 for details

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FF & JN
I don't think you need either the setup or teardown here.
* setupApp() without integration:true just creates a ETahi.Test object for sticking test globals in.
* ETahi.reset() resets the app's routes and clears out its container, both of which probably only get used in an integration test.  

I think.  Try it out. Good to see a test, though!