Add golint to test (#255)

* Add a new lint rule to the Makefile

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>

* Fix linter errors

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>

* Allow replacing the default apt mirror

Signed-off-by: Kenfe-Mickael Laventure <mickael.laventure@gmail.com>

supervisor/get_containers.go

@@ -2,6 +2,8 @@ package supervisor
 
 import "github.com/docker/containerd/runtime"
 
+// GetContainersTask holds needed parameters to retrieve a list of
+// containers
 type GetContainersTask struct {
 	baseTask
 	ID         string