Also show the command that run_management_command is running
Fix a bug in run_management_command: pass on all arguments
Don't try to capture stdout in update_za_hansard.bash

This produced confusing output, since stdout and stderr end up
mixed.  When we're confident this is running correctly, it would
be good to instead wrap the running of update_za_hansard.bash
in something like:

  https://github.com/mhl/output-on-error/blob/master/output-on-error