Manual: new security considerations chapter; VRDE/VRDP

Manual: use sed magic instead of XInclude to cobble together the translateable changelog implementation and still have it work with PDF and CHM

Manual: repair CHM creation, which omitted the changelog except for the first version. For reasons not completely understood yet, nested XInclude's don't work with the CHM creation, so do not nest the XIncludes for now but include user_ChangeLogImpl.xml directly from the top level.

export the manual to OSE