Add a mirror notice in the footer

lib/template.go

@@ -19,6 +19,7 @@ import (
 type Status struct {
 	BaseURL  string
 	FullURL  string
+	IsOnion  bool
 	Title    string
 	Search   string
 	User     string
@@ -42,6 +43,7 @@ func GetStatus(h handler) Status {
 		s.BaseURL = "http://" + host
 	}
 	s.FullURL = s.BaseURL + h.r.RequestURI
+	s.IsOnion = strings.HasSuffix(host, ".onion")
 	s.Title = "Imperial Library of Trantor"
 	s.User = h.sess.User
 	s.Role = h.sess.Role