Change id generation algorithm, display notifications total on the main page

server/db/migrations/20180721220409_create_user_table.js

@@ -0,0 +1,25 @@
+module.exports.up = knex =>
+  knex.schema
+    .createTable('user', table => {
+      /* Columns */
+
+      table
+        .bigInteger('id')
+        .primary()
+        .defaultTo(knex.raw('next_id()'));
+
+      table.text('email').notNullable();
+      table.text('password').notNullable();
+      table.boolean('is_admin').notNullable();
+      table.text('name').notNullable();
+      table.text('avatar');
+
+      table.timestamp('created_at', true);
+      table.timestamp('updated_at', true);
+      table.timestamp('deleted_at', true);
+    })
+    .raw(
+      'ALTER TABLE "user" ADD CONSTRAINT "user_email_unique" EXCLUDE ("email" WITH =) WHERE ("deleted_at" IS NULL)'
+    );
+
+module.exports.down = knex => knex.schema.dropTable('user');