Update README.md

Update travis-ci build link
have to chown root too
use maas_creds consistently. store ip in creds file, construct URL in authenticate_maas
create juju path
fix maas api url
uninstall - do not attempt to juju destroy on host machine

On single install everything is handled in a container, fix
up uninstall script to reflect that.

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
support logging into container to run status if single

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
fix another script name

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
better logging for container_cp

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>