Add app.json for heroku demo deploy
Add app.json for heroku demo deploy

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jordan-brough/solidus,jordan-brough/solidus,pervino/solidus,jordan-brough/solidus,pervino/solidus,pervino/solidus,Arpsara/solidus,jordan-brough/solidus,Arpsara/solidus,Arpsara/solidus,pervino/solidus,Arpsara/solidus