Add links to the commit pages (again) which point to the full sources of the changed files (BB-3243)

Previously you could click on the url of a changed file right above the section showing the changes for this file, and it would take you to the full source.
Now it just takes you to the version history for that file, and theres no simple way to get to the source anymore.

Please revert that change, or add another link to access the source.