Fix link variables with extended port specs

Signed-off-by: Maxime Petazzoni <max@signalfuse.com>
Pass in create_local_bind_dirs=True on container start

Requires a version of docker-py that supports it.

Signed-off-by: Maxime Petazzoni <max@signalfuse.com>
Catch APIError exceptions and display the error message

Signed-off-by: Maxime Petazzoni <max@signalfuse.com>