using flag-icons

the original flags come from a website that is not maintained.
using svg instead of png

flags used:
https://gitlab.com/catamphetamine/country-flag-icons

remove unused 'selected plane flag' code

Co-authored-by: Matthias Wirth <matthias.wirth@gmail.com>

88-tar1090.conf

@@ -79,7 +79,7 @@ $HTTP["url"] =~ "^/INSTANCE/images" {
         "Cache-Control" => "public, max-age=1209600",
         )
 }
-$HTTP["url"] =~ "^/INSTANCE/flags-tiny" {
+$HTTP["url"] =~ "^/INSTANCE/flags" {
     setenv.add-response-header += (
         "Cache-Control" => "public, max-age=1209600",
         )

html/defaults.js

@@ -220,8 +220,8 @@ let PageName = "tar1090";
 // Show country flags by ICAO addresses?
 let ShowFlags = true;
 
-// Path to country flags (can be a relative or absolute URL; include a trailing /)
-let FlagPath = "flags-tiny/";
+// UNUSED, kept here so config.js doesn't break for potential users
+let FlagPath = "";
 
 // Set to false to disable the ChartBundle base layers (US coverage only)
 let ChartBundleLayers = true;