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/mitchellh/mapstructure/decode_hooks.go

@@ -38,12 +38,6 @@ func DecodeHookExec(
 	raw DecodeHookFunc,
 	from reflect.Type, to reflect.Type,
 	data interface{}) (interface{}, error) {
-	// Build our arguments that reflect expects
-	argVals := make([]reflect.Value, 3)
-	argVals[0] = reflect.ValueOf(from)
-	argVals[1] = reflect.ValueOf(to)
-	argVals[2] = reflect.ValueOf(data)
-
 	switch f := typedDecodeHook(raw).(type) {
 	case DecodeHookFuncType:
 		return f(from, to, data)
@@ -121,6 +115,11 @@ func StringToTimeDurationHookFunc() DecodeHookFunc {
 	}
 }
 
+// WeaklyTypedHook is a DecodeHookFunc which adds support for weak typing to
+// the decoder.
+//
+// Note that this is significantly different from the WeaklyTypedInput option
+// of the DecoderConfig.
 func WeaklyTypedHook(
 	f reflect.Kind,
 	t reflect.Kind,
@@ -132,9 +131,8 @@ func WeaklyTypedHook(
 		case reflect.Bool:
 			if dataVal.Bool() {
 				return "1", nil
-			} else {
-				return "0", nil
 			}
+			return "0", nil
 		case reflect.Float32:
 			return strconv.FormatFloat(dataVal.Float(), 'f', -1, 64), nil
 		case reflect.Int: