Use is_readable() check instead of insufficient file_exists() for config includes.

Provision/Config/Drupal/provision_drupal_settings.tpl.php

@@ -144,11 +144,11 @@ if (isset($_SERVER['db_name'])) {
 <?php print $extra_config; ?>
 
   # Additional host wide configuration settings. Useful for safely specifying configuration settings.
-  if (file_exists('<?php print $this->platform->server->include_path  ?>/global.inc')) {
+  if (is_readable('<?php print $this->platform->server->include_path  ?>/global.inc')) {
     include_once('<?php print $this->platform->server->include_path  ?>/global.inc');
   }
 
   # Additional site configuration settings.
-  if (file_exists('<?php print $this->site_path  ?>/local.settings.php')) {
+  if (is_readable('<?php print $this->site_path  ?>/local.settings.php')) {
     include_once('<?php print $this->site_path  ?>/local.settings.php');
   }

http/Provision/Config/Apache/platform.tpl.php

@@ -8,7 +8,7 @@
 
 
 <?php
-  if (file_exists("{$this->root}/.htaccess")) {
+  if (is_readable("{$this->root}/.htaccess")) {
     print "\n# Include the platform's htaccess file\n";
     print "Include {$this->root}/.htaccess\n";
   }

platform/provision_drupal.drush.inc

@@ -78,7 +78,7 @@ function provision_drupal_drush_exit() {
  *   If the file exists, return TRUE, else return FALSE.
  */
 function _provision_drupal_site_exists() {
-  return file_exists(d()->site_path . '/settings.php');
+  return is_readable(d()->site_path . '/settings.php');
 }
 
 /**