Snap on Xubuntu

@pumuckll The lastest kernel has fixed the problems with squashfs and snap.

You can update the kernel with:

$ sudo apt-get update
$ sudo apt-get install linux-4.4-lastest

After reboot, install snap package by:

$ sudo apt-get update
$ sudo apt-get install snapd
$ sudo apt-get install snapcraft

$ snap install hello-world