Re: www/serf install permissions fix

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

> One potential pitfall would be that the work directory might be left 
> in that state if an error occurs during the extraction or fix-up such 
> that the work directory is not restored to {group,world}-searchable. 
Create a non-{g,w}-searchable subdir, extract there and move the contents 
back up to the work directory after fixing the extracted permissions?
Or just keep the extracted files in the subdir---this would also guard 
against upstream archives including .tools or the like.