Update dependencies

* Updates netlink/netns
* Updates x/sys, arkade and apimachinery

Build passes, minor updates.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

vendor/github.com/mitchellh/mapstructure/mapstructure.go

@@ -192,7 +192,7 @@ type DecodeHookFuncType func(reflect.Type, reflect.Type, interface{}) (interface
 // source and target types.
 type DecodeHookFuncKind func(reflect.Kind, reflect.Kind, interface{}) (interface{}, error)
 
-// DecodeHookFuncRaw is a DecodeHookFunc which has complete access to both the source and target
+// DecodeHookFuncValue is a DecodeHookFunc which has complete access to both the source and target
 // values.
 type DecodeHookFuncValue func(from reflect.Value, to reflect.Value) (interface{}, error)
 
@@ -258,6 +258,11 @@ type DecoderConfig struct {
 	// The tag name that mapstructure reads for field names. This
 	// defaults to "mapstructure"
 	TagName string
+
+	// MatchName is the function used to match the map key to the struct
+	// field name or tag. Defaults to `strings.EqualFold`. This can be used
+	// to implement case-sensitive tag values, support snake casing, etc.
+	MatchName func(mapKey, fieldName string) bool
 }
 
 // A Decoder takes a raw interface value and turns it into structured
@@ -376,6 +381,10 @@ func NewDecoder(config *DecoderConfig) (*Decoder, error) {
 		config.TagName = "mapstructure"
 	}
 
+	if config.MatchName == nil {
+		config.MatchName = strings.EqualFold
+	}
+
 	result := &Decoder{
 		config: config,
 	}
@@ -1340,7 +1349,7 @@ func (d *Decoder) decodeStructFromMap(name string, dataVal, val reflect.Value) e
 					continue
 				}
 
-				if strings.EqualFold(mK, fieldName) {
+				if d.config.MatchName(mK, fieldName) {
 					rawMapKey = dataValKey
 					rawMapVal = dataVal.MapIndex(dataValKey)
 					break