`deis apps:run` should receive stderr

[deis-admin]

From @mboersma on July 22, 2015 16:2

@Joshua-Anderson pointed out that deis run doesn't return stderr. At first glance, it looks like the canonical implementation for fleet could call paramiko's makefile_stderr function to do so. This would require similar, possibly backward-incompatible changes in the other schedulers (or no-ops), and probably in the controller models, REST API, and client(s).

Copied from original issue: deis/deis#4085

[deis-admin]

From @laurrentt on December 1, 2015 20:50

I know we're slowly getting away from fleet but I got a fix for this one if you're interested:

            def _do_ssh(cmd):
                with tran.open_session() as chan:
                    chan.get_pty() # <--- this make the stderr to show up (in order) in the output 
                    chan.exec_command(cmd)