Move sdk structs to modules/structs (#6905)

* move sdk structs to moduels/structs

* fix tests

* fix fmt

* fix swagger

* fix vendor

modules/structs/issue_milestone.go

@@ -0,0 +1,39 @@
+// Copyright 2016 The Gogs 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 structs
+
+import (
+	"time"
+)
+
+// Milestone milestone is a collection of issues on one repository
+type Milestone struct {
+	ID           int64     `json:"id"`
+	Title        string    `json:"title"`
+	Description  string    `json:"description"`
+	State        StateType `json:"state"`
+	OpenIssues   int       `json:"open_issues"`
+	ClosedIssues int       `json:"closed_issues"`
+	// swagger:strfmt date-time
+	Closed *time.Time `json:"closed_at"`
+	// swagger:strfmt date-time
+	Deadline *time.Time `json:"due_on"`
+}
+
+// CreateMilestoneOption options for creating a milestone
+type CreateMilestoneOption struct {
+	Title       string `json:"title"`
+	Description string `json:"description"`
+	// swagger:strfmt date-time
+	Deadline *time.Time `json:"due_on"`
+}
+
+// EditMilestoneOption options for editing a milestone
+type EditMilestoneOption struct {
+	Title       string     `json:"title"`
+	Description *string    `json:"description"`
+	State       *string    `json:"state"`
+	Deadline    *time.Time `json:"due_on"`
+}