def write(failed_libraries=[])
      latest = latest_hashes
      failed_libraries.each {|e| latest.delete(e) }
      save_marshal_index Marshal.dump([Boson.libraries, Boson.commands, latest])
    end
def write(failed_libraries=[])
      latest = latest_hashes
      failed_libraries.each {|e| latest.delete(e) }
      save_marshal_index Marshal.dump([Boson.libraries, Boson.commands, latest])
    end
Writes/saves current index to config/index.marshal.