Set time zone on Raspberry pi

Run this command which should work in most of distro.
Select the correct Zone that you wish to apply:

Example (London):

cp /usr/share/zoneinfo/Europe/London /etc/localtime

How to re-enable the systray (indicator panel) on Ubuntu 14.04

Installation in the terminal:

sudo apt-add-repository ppa:fixnix/indicator-systemtray-unity
sudo apt-get update
sudo apt-get install indicator-systemtray-unity

Once installed, you can enable it by this command:

gsettings list-recursively net.launchpad.indicator.systemtray

If you wish to remove it, run this command:

sudo apt-get --purge remove indicator-systemtray-unity