Keen Modding Live - Adjusted version tree in Abiathar Live Studio

My original rendition of the version selection dialog for Abiathar Live Studio assumed that an approved/visible version could never be derived from an unapproved/hidden one. Its call to the "get versions" API supplied the "approved versions only" switch when appropriate, so it didn't even get the hidden versions. (I might either remove that API switch or change it so that a useful tree can be constructed from its response.) I adjusted Abiathar Live Studio's tree generation code to request all versions of the level but cut hidden ones out of the lineage while keeping relationships between approved versions intact, just like the level info page on the web.