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`)

vendor/github.com/docker/libcompose/yaml/command.go

@@ -0,0 +1,42 @@
+package yaml
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/docker/docker/api/types/strslice"
+	"github.com/flynn/go-shlex"
+)
+
+// Command represents a docker command, can be a string or an array of strings.
+type Command strslice.StrSlice
+
+// UnmarshalYAML implements the Unmarshaller interface.
+func (s *Command) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var stringType string
+	if err := unmarshal(&stringType); err == nil {
+		parts, err := shlex.Split(stringType)
+		if err != nil {
+			return err
+		}
+		*s = parts
+		return nil
+	}
+
+	var sliceType []interface{}
+	if err := unmarshal(&sliceType); err == nil {
+		parts, err := toStrings(sliceType)
+		if err != nil {
+			return err
+		}
+		*s = parts
+		return nil
+	}
+
+	var interfaceType interface{}
+	if err := unmarshal(&interfaceType); err == nil {
+		fmt.Println(interfaceType)
+	}
+
+	return errors.New("Failed to unmarshal Command")
+}