update async module
update async module

hildjj/nodeunit,caolan/nodeunit,hildjj/nodeunit,robert-berg/rjberg-nodeunit,ExtPoint/extnodeunit,caolan/nodeunit,sethmcl/nodeunit,zuazo-forks/nodeunit,BuZZ-dEE/nodeunit,BuZZ-dEE/nodeunit,isaacs/nodeunit,1602/nodeunit,ExtPoint/extnodeunit,sethmcl/nodeunit