Update traefik dependencies (docker/docker and related) (#1823)

Update traefik dependencies (docker/docker and related)

- Update dependencies
- Fix compilation problems
- Remove vdemeester/docker-events (in docker api now)
- Remove `integration/vendor`
- Use `testImport`
- update some deps.
- regenerate the lock from scratch (after a `glide cc`)

integration/vendor/github.com/libkermit/docker/clean.go

@@ -1,20 +0,0 @@
-package docker
-
-// Clean stops and removes (by default, controllable with the keep) kermit containers
-func (p *Project) Clean(keep bool) error {
-	containers, err := p.List()
-	if err != nil {
-		return err
-	}
-	for _, container := range containers {
-		if err := p.StopWithTimeout(container.ID, 1); err != nil {
-			return err
-		}
-		if !keep {
-			if err := p.Remove(container.ID); err != nil {
-				return err
-			}
-		}
-	}
-	return nil
-}