Add XML payload support

Fixes #238

vendor/github.com/clbanning/mxj/remove.go

@@ -0,0 +1,37 @@
+package mxj
+
+import "strings"
+
+// Removes the path.
+func (mv Map) Remove(path string) error {
+	m := map[string]interface{}(mv)
+	return remove(m, path)
+}
+
+func remove(m interface{}, path string) error {
+	val, err := prevValueByPath(m, path)
+	if err != nil {
+		return err
+	}
+
+	lastKey := lastKey(path)
+	delete(val, lastKey)
+
+	return nil
+}
+
+// returns the last key of the path.
+// lastKey("a.b.c") would had returned "c"
+func lastKey(path string) string {
+	keys := strings.Split(path, ".")
+	key := keys[len(keys)-1]
+	return key
+}
+
+// returns the path without the last key
+// parentPath("a.b.c") whould had returned "a.b"
+func parentPath(path string) string {
+	keys := strings.Split(path, ".")
+	parentPath := strings.Join(keys[0:len(keys)-1], ".")
+	return parentPath
+}