Fix #413. Exclude Let's Encrypt bot from blacklisted bots

.htaccess.disabled

@@ -1,3 +1,4 @@
 RewriteEngine on
+RewriteCond !%{HTTP_USER_AGENT} "Let's Encrypt validation server" [NC]
 RewriteCond %{HTTP_USER_AGENT} ^.*(bot|spider|crawl|https?://|WhatsApp|SkypeUriPreview|facebookexternalhit) [NC]
 RewriteRule .* - [R=403,L]