Added multilanguage support

vendor/github.com/nicksnyder/go-i18n/v2/internal/plural/rules.go

@@ -0,0 +1,24 @@
+package plural
+
+import "golang.org/x/text/language"
+
+// Rules is a set of plural rules by language tag.
+type Rules map[language.Tag]*Rule
+
+// Rule returns the closest matching plural rule for the language tag
+// or nil if no rule could be found.
+func (r Rules) Rule(tag language.Tag) *Rule {
+	t := tag
+	for {
+		if rule := r[t]; rule != nil {
+			return rule
+		}
+		t = t.Parent()
+		if t.IsRoot() {
+			break
+		}
+	}
+	base, _ := tag.Base()
+	baseTag, _ := language.Parse(base.String())
+	return r[baseTag]
+}