upgrade kernel from v3.16.2 to v3.16.3
Revert "XZ utils is required by tar"

This reverts commit ce265a569c5e8d32de3b8ea78aa16abf68a962c7.

xz-util should be xz-utils here, and according to this list, http://releases.ubuntu.com/releases/trusty/ubuntu-14.04-desktop-amd64.manifest, it's already in it, since we bumped the ubuntu version, we don't need to install it by ourselves anymore.
Merge branch 'PeterDaveHello-kernel_upgrade'
Merge pull request #47 from PeterDaveHello/update_readme

Revert "XZ utils is required by tar"
upgrade linux_firmware