Add hide activity option (#11353)

* Add hide activity option

This closes https://github.com/go-gitea/gitea/issues/7927

* Adjust for linter

* Adjust for linter

* Add tests

* Remove info that admins can view the activity

* Adjust new tests for linter

* Rename v139.go to v140.go

* Rename v140.go to v141.go

* properly indent

* gofmt

Co-authored-by: Jonas Lochmann <git@inkompetenz.org>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

models/migrations/v141.go

@@ -0,0 +1,22 @@
+// Copyright 2020 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 migrations
+
+import (
+	"fmt"
+
+	"xorm.io/xorm"
+)
+
+func addKeepActivityPrivateUserColumn(x *xorm.Engine) error {
+	type User struct {
+		KeepActivityPrivate bool
+	}
+
+	if err := x.Sync2(new(User)); err != nil {
+		return fmt.Errorf("Sync2: %v", err)
+	}
+	return nil
+}