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/inspect.go

@@ -1,17 +0,0 @@
-package docker
-
-import (
-	"golang.org/x/net/context"
-
-	"github.com/docker/engine-api/types"
-)
-
-// Inspect returns the container informations
-func (p *Project) Inspect(containerID string) (types.ContainerJSON, error) {
-	container, err := p.Client.ContainerInspect(context.Background(), containerID)
-	if err != nil {
-		return types.ContainerJSON{}, err
-	}
-
-	return container, nil
-}