Reverted work on revisions

Improved linkage of drawings and image manager.
Updated image updates to create new versions.

database/migrations/2018_05_13_090521_create_image_revisions_table.php

@@ -1,38 +0,0 @@
-<?php
-
-use Illuminate\Support\Facades\Schema;
-use Illuminate\Database\Schema\Blueprint;
-use Illuminate\Database\Migrations\Migration;
-
-class CreateImageRevisionsTable extends Migration
-{
-    /**
-     * Run the migrations.
-     *
-     * @return void
-     */
-    public function up()
-    {
-        Schema::create('image_revisions', function (Blueprint $table) {
-            $table->increments('id');
-            $table->integer('image_id');
-            $table->integer('revision');
-            $table->string('path');
-            $table->string('url');
-            $table->integer('created_by');
-
-            $table->index('image_id');
-            $table->timestamps();
-        });
-    }
-
-    /**
-     * Reverse the migrations.
-     *
-     * @return void
-     */
-    public function down()
-    {
-        Schema::dropIfExists('image_revisions');
-    }
-}