[#6837] Translate rev links when importing from Trac

Also fixed a couple of issues with handling of ticket links and
escaping brackets in link text

Signed-off-by: Cory Johns <cjohns@slashdotmedia.com>
[#6837] Strip trailing question mark from "missing wiki" links

Signed-off-by: Cory Johns <cjohns@slashdotmedia.com>