FEATURE: make user id not mandatory in widgets table

database/migrations/2016_09_24_220747_MakeUserIdNullableAtWidgets.php

@@ -0,0 +1,55 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+
+class MakeUserIdNullableAtWidgets extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        Schema::table('widgets', function (Blueprint $table) {
+
+                $table->dropForeign(['user_id']);
+
+            $table->integer('user_id')
+                  ->nullable(true)
+                  ->default(null)
+                  ->comment('User ID who created this widget. NULL for widget created by template.')->change();
+
+            $table->foreign('user_id')
+                  ->references('id')
+                  ->on('users')
+                  ->onDelete('cascade')
+                  ->onUpdate('cascade');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        Schema::table('widgets', function (Blueprint $table) {
+            $table->dropForeign(['user_id']);
+        });
+
+        Schema::table('widgets', function (Blueprint $table) {
+            $table->integer('user_id')
+                  ->nullable(false)
+                  ->comment('User ID who created this widget. ')->change();
+
+            $table->foreign('user_id')
+                  ->references('id')
+                  ->on('users')
+                  ->onDelete('no action')
+                  ->onUpdate('no action');
+        });
+    }
+}