Add contactable to tracks

Added social media fields to track submission form
by using a polymorphic association with the
Contact Model.

db/migrate/20190612161235_add_polymorphic_to_contact.rb

@@ -0,0 +1,6 @@
+class AddPolymorphicToContact < ActiveRecord::Migration[5.1]
+  def change
+    add_column :contacts, :contactable_type, :string
+    add_column :contacts, :contactable_id, :integer
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2019_06_03_143107) do
+ActiveRecord::Schema.define(version: 2019_06_12_161235) do
 
   create_table "answers", force: :cascade do |t|
     t.string "title"
@@ -126,6 +126,8 @@ ActiveRecord::Schema.define(version: 2019_06_03_143107) do
     t.string "mastodon"
     t.string "youtube"
     t.string "blog"
+    t.string "contactable_type"
+    t.integer "contactable_id"
   end
 
   create_table "delayed_jobs", force: :cascade do |t|