Issue #2036689 by batigolix, babruix, linclark: Create hook_help() for Serialization module.

core/modules/serialization/serialization.module

 <?php
+
+/**
+ * Implements hook_help().
+ */
+function serialization_help($path, $arg) {
+  switch ($path) {
+    case 'admin/help#serialization':
+      $output = '';
+      $output .= '<h3>' . t('About') . '</h3>';
+      $output .= '<p>' . t('The Serialization module provides a service for serializing and deserializing data to and from formats such as JSON and XML.') . '</p>';
+      $output .= '<p>' . t('Serialization is the process of converting data structures like arrays and objects into a string. This allows the data to be represented in a way that is easy to exchange and store (for example, for transmission over the Internet or for storage in a local file system). These representations can then be deserialized to get back to the original data structures.') . '</p>';
+      $output .= '<p>' . t('The serializer splits this process into two parts. Normalization converts an object to a normalized array structure. Encoding takes that array and converts it to a string.') . '</p>';
+      $output .= '<p>' . t('This module does not have a user interface. It is used by other modules which need to serialize data, such as <a href="!rest">REST</a>.', array('!rest' => \Drupal::url('help.page', array('name' => 'rest')))) . '</p>';
+      $output .= '<p>' . t('For more information, see the <a href="!doc_url">online documentation for the Serialization module</a>.', array('!doc_url' => 'https://drupal.org/documentation/modules/serialization')) . '</p>';
+      return $output;
+  }
+}