Add reminder feature

db/migrate/20200212122724_create_reminders.rb

@@ -0,0 +1,12 @@
+class CreateReminders < ActiveRecord::Migration[6.0]
+  def change
+    create_table :reminders do |t|
+      t.string :title
+      t.text :body
+      t.datetime :date
+      t.references :user, null: false, foreign_key: true
+
+      t.timestamps
+    end
+  end
+end