Support localized templates for flagging

[lahwaacz]

There are translated versions for Template:Broken section link and Template:Dead link, they should be supported the same way as translations of Template:Broken package link.

Furthermore, there may be localized redirects pointing to the translated versions. They should be supported when checking if a link is flagged or not.

[lahwaacz]

This was fixed in a7f1106, 338aa3b, ba3ba9f and maybe some older commits. Localized redirects will not be supported.