V3.53 - We fixed the bug related to 'docx' mime type. We changed plugin settings page displaying. Added an ability to delete an attachment file from the server after the email is sent. The Slovak language file is added. The French language file is updated.

git-svn-id: https://plugins.svn.wordpress.org/contact-form-plugin/trunk@759160 b8457f37-d9ea-0310-8a92-e5e31aec5664