Move modules/forms to services/forms (#15305)

Forms are dependent on models and therefore should be in services.

This PR also removes the old auth. aliasing

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

services/forms/repo_branch_form.go

@@ -0,0 +1,26 @@
+// 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 forms
+
+import (
+	"net/http"
+
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/web/middleware"
+
+	"gitea.com/go-chi/binding"
+)
+
+// NewBranchForm form for creating a new branch
+type NewBranchForm struct {
+	NewBranchName string `binding:"Required;MaxSize(100);GitRefName"`
+	CreateTag     bool
+}
+
+// Validate validates the fields
+func (f *NewBranchForm) Validate(req *http.Request, errs binding.Errors) binding.Errors {
+	ctx := context.GetContext(req)
+	return middleware.Validate(errs, ctx.Data, f, ctx.Locale)
+}