Merge pull request #2213 from zoghal/2.x-fixme

add mkv mime file type

lib/Cake/Network/CakeResponse.php

@@ -300,6 +300,7 @@ class CakeResponse {
 		'webapp' => 'application/x-web-app-manifest+json',
 		'vcf' => 'text/x-vcard',
 		'vtt' => 'text/vtt',
+		'mkv' => 'video/x-matroska',
 	);
 
 /**