Post to Slack (#603)

* Migrations

* WIP: Integration model, slack perms / hooks

* So so rough it pains me. Building this new model is revealing just how much needs to be refactored

* Working connect and post

* Cleanup UI, upating documents

* Show when slack command is connected

* stash

* 💚

* Add documents.update trigger

* Authorization, tidying

* Fixed integration policy

* pick integration presenter keys

server/models/Integration.js

@@ -0,0 +1,35 @@
+// @flow
+import { DataTypes, sequelize } from '../sequelize';
+
+const Integration = sequelize.define('integration', {
+  id: {
+    type: DataTypes.UUID,
+    defaultValue: DataTypes.UUIDV4,
+    primaryKey: true,
+  },
+  type: DataTypes.STRING,
+  serviceId: DataTypes.STRING,
+  settings: DataTypes.JSONB,
+  events: DataTypes.ARRAY(DataTypes.STRING),
+});
+
+Integration.associate = models => {
+  Integration.belongsTo(models.User, {
+    as: 'user',
+    foreignKey: 'userId',
+  });
+  Integration.belongsTo(models.Team, {
+    as: 'team',
+    foreignKey: 'teamId',
+  });
+  Integration.belongsTo(models.Collection, {
+    as: 'collection',
+    foreignKey: 'collectionId',
+  });
+  Integration.belongsTo(models.Authentication, {
+    as: 'authentication',
+    foreignKey: 'authenticationId',
+  });
+};
+
+export default Integration;