Use popover to edit task and description directly from board.

- Click on 'description' icon opens the 'edit-description' page.
- Edit task and edit description now open in popover, like the assign
dialog.

app/Templates/task_edit.php

@@ -1,12 +1,14 @@
 <section id="main">
     <div class="page-header">
         <h2><?= t('Edit a task') ?></h2>
+<?php if (!$ajax): ?>
         <ul>
             <li><a href="?controller=board&amp;action=show&amp;project_id=<?= $task['project_id'] ?>"><?= t('Back to the board') ?></a></li>
         </ul>
+<?php endif ?>
     </div>
     <section>
-    <form method="post" action="?controller=task&amp;action=update&amp;task_id=<?= $task['id'] ?>" autocomplete="off">
+    <form method="post" action="?controller=task&amp;action=update&amp;task_id=<?= $task['id'] ?>&amp;ajax=<?= $ajax ?>" autocomplete="off">
 
         <?= Helper\form_csrf() ?>
 
@@ -47,7 +49,12 @@
 
         <div class="form-actions">
             <input type="submit" value="<?= t('Save') ?>" class="btn btn-blue"/>
-            <?= t('or') ?> <a href="?controller=task&amp;action=show&amp;task_id=<?= $task['id'] ?>"><?= t('cancel') ?></a>
+            <?= t('or') ?>
+<?php if ($ajax): ?>
+            <a href="?controller=board&amp;action=show&amp;project_id=<?= $task['project_id'] ?>"><?= t('cancel') ?></a>
+<?php else: ?>
+            <a href="?controller=task&amp;action=show&amp;task_id=<?= $task['id'] ?>"><?= t('cancel') ?></a>
+<?php endif ?>
         </div>
     </form>
     </section>