Checkrestart is faster than needrestart for that, so why not using it?

Add an example for Disk and Inode usage in the README file

I forgot to change the README file when i added Inode Usage. This commit change the example.

See merge request !2

Add inode usage

I just added the inode usage below disk usage.

See merge request !1

Like this, installation fail (like on wheezy) won't prevent the
installation of the other packages