Update rust and move from wip/ to lang/ ?

[Martin Husemann <martin%duskware.de@localhost>]

Hey folks,

it would be really cool if someone(tm) could have a look at wip/rust and
update it (from 0.11 to 1.7 ;-}) and eventually make it move to lang/.

The firefox builds can make use of it in the near future (and may even
require it some later day, duh!)

Thanks,

Martin