New Cleaner: For Debian GNU/Linux re-branded Thunderbird email client.

Derived from Thunderbird cleaner by removing irrelevant MS Windows items
and replacing thunderbird by icedove in nearly all search terms.
Tested with a Thunderbird 17.0.10 release on a Debian 7.3 based system.

Signed-off-by: Stephen Lyons <slysven@virginmedia.com>