Implement base notifications support (#77)

* initial implementation of notifications
* typehint UUID returns. Fixes that notifications bug

database/migrations/2016_09_04_182835_create_notifications_table.php

@@ -0,0 +1,34 @@
+<?php
+
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Migrations\Migration;
+
+class CreateNotificationsTable extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        Schema::create('notifications', function (Blueprint $table) {
+            $table->string('id')->primary();
+            $table->string('type');
+            $table->morphs('notifiable');
+            $table->text('data');
+            $table->timestamp('read_at')->nullable();
+            $table->timestamps();
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        Schema::drop('notifications');
+    }
+}