Bug#648249: zram script: use one zram device for each CPU

[Jeronimo Pellegrini <j_p@aleph0.info>]

Hello,

I instaled the Ubuntu script, and it works perfectly.

The script that Dmitry Smirnov presented also works, but creates 
only zram0.
The Ubuntu script creates one for each CPU (so that compressing
and decompressing work is spread among them). For an 8-core system,
for example, this may be really nice.

Also, it would be good to have a method not only to turn on zram,
but also to turn it off -- like "service zram stop". And having
"service status zram" available is also great.

And -- having it packaged as Ubuntu does helps make the whole system 
more consistent (using "service <whatever> action" for things that
can be turned on, off, enabled at startup is really a good thing, 
IMHO).

J.