Keen Modding Live - Play any version

For a while now, Keen Modding Live has supported multiple versions of a given level, but there was no way to actually play any version except the current one. Today I adjusted the player page to take a version ID rather than a level ID. Since people might want to share links to the level in its most recent version, the page can also take a level ID, in which case it automatically redirects to the current version. Now I need to implement a way to explore the versions of a given level.