Move old backend code to old_src folder

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

old_src/lib/migrations/20150702001020-update-to-0_3_1.js

@@ -0,0 +1,45 @@
+'use strict'
+module.exports = {
+  up: async function (queryInterface, Sequelize) {
+    return queryInterface.addColumn('Notes', 'shortid', {
+      type: Sequelize.STRING,
+      defaultValue: '0000000000',
+      allowNull: false
+    }).then(function () {
+      return queryInterface.addIndex('Notes', ['shortid'], {
+        indicesType: 'UNIQUE'
+      })
+    }).then(function () {
+      return queryInterface.addColumn('Notes', 'permission', {
+        type: Sequelize.STRING,
+        defaultValue: 'private',
+        allowNull: false
+      })
+    }).then(function () {
+      return queryInterface.addColumn('Notes', 'viewcount', {
+        type: Sequelize.INTEGER,
+        defaultValue: 0
+      })
+    }).catch(function (error) {
+      if (error.message === 'SQLITE_ERROR: duplicate column name: shortid' || error.message === "ER_DUP_FIELDNAME: Duplicate column name 'shortid'" || error.message === 'column "shortid" 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.removeColumn('Notes', 'viewcount')
+      .then(function () {
+        return queryInterface.removeColumn('Notes', 'permission')
+      })
+      .then(function () {
+        return queryInterface.removeIndex('Notes', ['shortid'])
+      })
+      .then(function () {
+        return queryInterface.removeColumn('Notes', 'shortid')
+      })
+  }
+}