Drupal: Add settings.local.php to main settings.php file. Added local settings to gitignore.

drupal/.gitignore

@@ -1 +1,2 @@
 sites/all/modules
+sites/default/settings.local.php

drupal/sites/default/settings.php

@@ -174,6 +174,18 @@ ini_set('upload_max_filesize', '8MB');
 #   'theme_default' => 'minnelli',
 #   'anonymous' => 'Visitor',
 # );
-$conf = array(
+
-  'maintenance_theme' => 'einstein',
+/**
-);
+ * Load local development override configuration, if available.
+ *
+ * Use settings.local.php to override variables on secondary (staging,
+ * development, etc) installations of this site. Typically used to disable
+ * caching, JavaScript/CSS compression, re-routing of outgoing emails, and
+ * other things that should not happen on development and testing sites.
+ *
+ * Keep this code block at the end of this file to take full effect.
+ */
+
+if (stream_resolve_include_path('settings.local.php')) {
+  include 'settings.local.php';
+}