Revert "Procedure: set archive_date to datetime to allow localtime"

This reverts commit 14dd75d0d2.

db/migrate/20170523081220_change_procedure_auto_archive_date_to_datetime.rb

@@ -1,9 +0,0 @@
-class ChangeProcedureAutoArchiveDateToDatetime < ActiveRecord::Migration[5.0]
-  def up
-    change_column :procedures, :auto_archive_on, :datetime
-  end
-
-  def down
-    change_column :procedures, :auto_archive_on, :date
-  end
-end

db/schema.rb

@@ -358,7 +358,7 @@ ActiveRecord::Schema.define(version: 20170523092900) do
     t.string   "lien_notice"
     t.boolean  "for_individual",        default: false
     t.boolean  "individual_with_siret", default: false
-    t.datetime "auto_archive_on"
+    t.date     "auto_archive_on"
   end
 
   create_table "quartier_prioritaires", force: :cascade do |t|