enhanced plugin support (#634)

- refactored admin controller and templates
- plugin support for entity actions
- changed column mail to email in customer table
- refactored theme events

src/Twig/EventExtensions.php

@@ -0,0 +1,83 @@
+<?php
+
+/*
+ * This file is part of the Kimai time-tracking app.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace App\Twig;
+
+use App\Entity\User;
+use App\Event\ThemeEvent;
+use App\Security\CurrentUser;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+use Twig\Extension\AbstractExtension;
+use Twig\TwigFunction;
+
+class EventExtensions extends AbstractExtension
+{
+    /**
+     * @var EventDispatcherInterface
+     */
+    protected $eventDispatcher;
+    /**
+     * @var User
+     */
+    protected $user;
+
+    /**
+     * @param EventDispatcherInterface $dispatcher
+     */
+    public function __construct(EventDispatcherInterface $dispatcher, CurrentUser $user)
+    {
+        $this->eventDispatcher = $dispatcher;
+        $this->user = $user->getUser();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getFunctions()
+    {
+        return [
+            new TwigFunction('trigger', [$this, 'triggerEvent']),
+        ];
+    }
+
+    /**
+     * @return EventDispatcherInterface
+     */
+    protected function getDispatcher()
+    {
+        return $this->eventDispatcher;
+    }
+
+    /**
+     * @param string $eventName
+     *
+     * @return bool
+     */
+    protected function hasListener($eventName)
+    {
+        return $this->getDispatcher()->hasListeners($eventName);
+    }
+
+    /**
+     * @param string $eventName
+     * @param mixed $payload
+     * @return ThemeEvent
+     */
+    public function triggerEvent(string $eventName, $payload = null)
+    {
+        $themeEvent = new ThemeEvent($this->user, $payload);
+
+        if ($this->hasListener($eventName)) {
+            $this->getDispatcher()->dispatch($eventName, $themeEvent);
+        }
+
+        return $themeEvent;
+    }
+
+}