geometric logs (DualOutputHandler) update to handle any arbitrary update function instead of just print_stdout

[coltonbh]

Update the DualOutputHandler to run arbitrary update functions to send logs anywhere. Have punted on this for now as it's not needed and will require some extra engineering work.

[coltonbh]

Probably better to just solve this by hoisting all update_func stuff to the BaseAdapter.compute() level and have all lower functions output their stdout to sys.stdout which I can capture in .compute() and run an update func in the background there. See #30 .