Add API to list tags (#5850)

* Add API to list tags

* update dependency gitea sdk vendor

* fix swagger generation

* fix swagger

* add tests

* update code.gitea.io/git vendor

models/repo_tag.go

@@ -0,0 +1,24 @@
+// Copyright 2019 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package models
+
+import (
+	"code.gitea.io/git"
+)
+
+// GetTagsByPath returns repo tags by it's path
+func GetTagsByPath(path string) ([]*git.Tag, error) {
+	gitRepo, err := git.OpenRepository(path)
+	if err != nil {
+		return nil, err
+	}
+
+	return gitRepo.GetTagInfos()
+}
+
+// GetTags return repo's tags
+func (repo *Repository) GetTags() ([]*git.Tag, error) {
+	return GetTagsByPath(repo.RepoPath())
+}