Added article

models/article.go

@@ -0,0 +1,13 @@
+package models
+
+type Article struct {
+	Id       string           `gorm:"primaryKey" json:"id"`
+	Author   User             `json:"author"`
+	Title    string           `json:"title"`
+	Sections []ArticleSection `gorm:"serializer:json" json:"sections"`
+}
+
+type ArticleSection struct {
+	Type    string `json:"type"`
+	Content string `json:"content"`
+}