ports collection background-fetch

[Wojciech Puchar]

> and on each one run 'make' for the port you want to compile.  The port(s) 
> will be fetched and compiled simultaneously.  Then all you need to do is to 
> run 'make install' for each port.
>
> Note: I'm not sure but I think it's not a good practice to issue more than

i do many but only one at normal priority, and other with nice -n 20