add rated on securityheaders.io

PrivateBin-Directory.md

@@ -6,7 +6,7 @@ URL | forced HTTPS | file upload | other
 ----|:------------:|:-----------:|------
 https://snip.dssr.ch | :white_check_mark: | :white_check_mark:
 https://privatebin.net | :white_check_mark: | :white_large_square:
-https://p.dousse.eu | :white_check_mark: | :white_check_mark: | No IP Logs, Let's Encrypt SSL, A+ rated on SSL Labs
+https://p.dousse.eu | :white_check_mark: | :white_check_mark: | No IP Logs, Let's Encrypt SSL, A+ rated on SSL Labs, A rated on securityheaders.io
 https://paste.unixcorn.org | :white_check_mark: | :white_large_square: | french / Français
 https://wtf.roflcopter.fr/paste/ | :white_check_mark: | :white_large_square:
 https://paste.biocrafting.net | :white_check_mark: | :white_large_square: | No IP Logs, Let's Encrypt SSL, HPKP, HSTS (preload)