🗃️ Ajoute les tags

Pour #1

database/migrations/2019_09_26_092440_create_tags.php

@@ -0,0 +1,42 @@
+<?php
+
+use Illuminate\Support\Facades\Schema;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Database\Migrations\Migration;
+
+class CreateTags extends Migration
+{
+    /**
+     * Run the migrations.
+     *
+     * @return void
+     */
+    public function up()
+    {
+        Schema::create('tags', function (Blueprint $table) {
+            $table->bigIncrements('id');
+            $table->timestamps();
+            $table->string('name')->unique();
+        });
+
+        Schema::create('posts_tags', function (Blueprint $table) {
+            $table->bigIncrements('id');
+            $table->timestamps();
+            $table->bigInteger('post_id');
+            $table->bigInteger('tag_id');
+            $table->foreign('post_id')->references('id')->on('posts');
+            $table->foreign('tag_id')->references('id')->on('tags');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     *
+     * @return void
+     */
+    public function down()
+    {
+        Schema::dropIfExists('tags');
+        Schema::dropIfExists('posts_tags');
+    }
+}