fix: Support SQlite

Move 'unique' constraint to another statement (SQLite don't support set unique when addColumn)

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

@@ -3,17 +3,22 @@ module.exports = {
   up: function (queryInterface, Sequelize) {
     return queryInterface.addColumn('Notes', 'shortid', {
       type: Sequelize.STRING,
-      unique: true,
+      defaultValue: '0000000000',
       allowNull: false
+    }).then(function () {
+      return queryInterface.addIndex('Notes', ['shortid'], {
+        indicesType: 'UNIQUE'
+      })
     }).then(function () {
       return queryInterface.addColumn('Notes', 'permission', {
         type: Sequelize.STRING,
-        allowNull: false,
-        defaultValue: 0
+        defaultValue: 'private',
+        allowNull: false
       })
     }).then(function () {
       return queryInterface.addColumn('Notes', 'viewcount', {
-        type: Sequelize.INTEGER
+        type: Sequelize.INTEGER,
+        defaultValue: 0
       })
     })
   },
@@ -23,6 +28,9 @@ module.exports = {
       .then(function () {
         return queryInterface.removeColumn('Notes', 'permission')
       })
+      .then(function () {
+        return queryInterface.removeIndex('Notes', ['shortid'])
+      })
       .then(function () {
         return queryInterface.removeColumn('Notes', 'shortid')
       })