python3: Add list_containers to C API

This adds a new list_containers function to the python3 binding and a
matching override in __init__.py that adds the as_object parameter.

This should be compatible to the previous pure python implementation
with the advantage of also listing active non-defined containers (fixing
github issue #68).

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>
python3: Code style

Drop any tab as spaces are preferred, get everything to fit the 80char
limit.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
python3: Sort all method/property lists

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
python3: Add reboot() to the binding

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
python3: Re-order all functions

This properly regroups the module functions together and then sorts all
other functions alphabetically to match the function and property lists.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
python3: Add clear_config() to the binding

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
python3: Add controllable property to the binding

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
python3: Add (add|remove)_device_node

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>