Revert "Abstracting the loading of files in the config directory depending on environments."

This reverts commit 5c1aa631c5f5ec2f6b75ba1158178418e50ba11a.
diff --git a/system/helpers/file_helper.php b/system/helpers/file_helper.php
index b4edcde..5b50853 100644
--- a/system/helpers/file_helper.php
+++ b/system/helpers/file_helper.php
@@ -364,7 +364,14 @@
 
 		if ( ! is_array($mimes))
 		{
-			load_environ_config('mimes');
+			if (defined('ENVIRONMENT') AND is_file(APPPATH.'config/'.ENVIRONMENT.'/mimes.php'))
+			{
+				include(APPPATH.'config/'.ENVIRONMENT.'/mimes.php');
+			}
+			elseif (is_file(APPPATH.'config/mimes.php'))
+			{
+				include(APPPATH.'config/mimes.php');
+			}
 
 			if ( ! is_array($mimes))
 			{