Use certbot for let's encrypt certificate
diff --git a/.gitignore b/.gitignore
index 6e6928b..7c47734 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,6 @@
+/certbot/lib/
+/certbot/www/
+/certs/
 /environment
 /gerrit/environment
 /gerrit/cache/
@@ -5,6 +8,7 @@
 /gerrit/etc/
 /gerrit/git/
 /gerrit/index/
+/logs/certbot/
 /logs/gerrit/
 /logs/nginx/
 /logs/simpleid/