Right now, we add the url of the source to the version historyedit summary, but this might not always work, e.g. if the url is longer than the edit summary limit.
Add a link to the edit summary message, that allows users to always be able to find the origin of a file.
TODO DESIGN: Mock what should be the link The url in the edit summary is a link to that url
 If the url in the edit summary is cut off, the link is still intact.