provide an interface to access generated output more as a stream

that's a tricky one. for an example i'd need a well known command that generates stdout while running (and not only prints at the end), the process could be `print` (maybe even `print` with  `FH` as arguments to create an intermediate log file).
the nice thing to have would be a stream logger, like we have in `fancylogger`, then we can use it in e.g. `spma` while yum is doing things. is it possible to access the filehandle of the logger?