Move old backend code to old_src folder

Signed-off-by: David Mehren <git@herrmehren.de>

old_src/lib/migrations/20160703062241-support-authorship.js

@@ -0,0 +1,36 @@
+'use strict'
+module.exports = {
+  up: async function (queryInterface, Sequelize) {
+    return queryInterface.addColumn('Notes', 'authorship', Sequelize.TEXT).then(function () {
+      return queryInterface.addColumn('Revisions', 'authorship', Sequelize.TEXT)
+    }).then(function () {
+      return queryInterface.createTable('Authors', {
+        id: {
+          type: Sequelize.INTEGER,
+          primaryKey: true,
+          autoIncrement: true
+        },
+        color: Sequelize.STRING,
+        noteId: Sequelize.UUID,
+        userId: Sequelize.UUID,
+        createdAt: Sequelize.DATE,
+        updatedAt: Sequelize.DATE
+      })
+    }).catch(function (error) {
+      if (error.message === 'SQLITE_ERROR: duplicate column name: authorship' || error.message === "ER_DUP_FIELDNAME: Duplicate column name 'authorship'" || error.message === 'column "authorship" of relation "Notes" already exists') {
+        // eslint-disable-next-line no-console
+        console.log('Migration has already run… ignoring.')
+      } else {
+        throw error
+      }
+    })
+  },
+
+  down: async function (queryInterface, Sequelize) {
+    return queryInterface.dropTable('Authors').then(function () {
+      return queryInterface.removeColumn('Revisions', 'authorship')
+    }).then(function () {
+      return queryInterface.removeColumn('Notes', 'authorship')
+    })
+  }
+}