Make the help, bug tracker, and donation URLs available to the backends, and display them on the App page.
Also, expose the help URL on the Application page, so users can easily find the app's documentation. The other URLs will probably require a bit more UI design work to avoid overloading the metadata sectionCurrently working on a better design to make the metadata section not look so intimidating for apps that behave well and expose all these URLs--but that can go in later, so I didn't expossince them in the UI yet in this patchis has to land on master.