refactor: remove workaround after the golang 1.7 release. (#1349)

* refactor: remove workaround after the golang 1.7 release.

* remove unused import.

Signed-off-by: Bo-Yi Wu <appleboy.tw@gmail.com>

* refactor: Add remove function.

* refactor: rename

* refactor: update build flag

modules/util/remove_windows.go

@@ -0,0 +1,16 @@
+// +build windows,!go1.7
+
+// Copyright 2017 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 util
+
+// RemoveAll files from path on windows
+// workaround for Go not being able to remove read-only files/folders: https://github.com/golang/go/issues/9606
+// this bug should be fixed on Go 1.7, so the workaround should be removed when Gitea don't support Go 1.6 anymore:
+// https://github.com/golang/go/commit/2ffb3e5d905b5622204d199128dec06cefd57790
+func RemoveAll(path string) error {
+	path = strings.Replace(path, "/", "\\", -1)
+	return exec.Command("cmd", "/C", "rmdir", "/S", "/Q", path).Run()
+}