Set App Property

Sets the value of an app's property. Use this resource to store custom data for your app.The value of the request body must be a [valid](http://tools.ietf.org/html/rfc4627), non-empty JSON blob. The maximum length is 32768 characters.**[Permissions](#permissions) required:** Only a Connect app whose key matches `addonKey` can make this request.Additionally, Forge apps can access Connect app properties (stored against the same `app.connect.key`).