Show All Icons/Indicators in Unity Panel’s Notification Area

Install dconf-editor:
sudo apt-get install dconf-tools

Run dconf-editor
Alt+F2 and enter dconf-editor

desktop > unity > panel

Change:
systray-whitelist ['JavaEmbeddedFrame', 'Mumble', 'Wine', 'Skype', 'hp-systray', 'scp-dbus-service']

to:
systray-whitelist ['all']

Refresh Unity:
Alt+F2 and enter unity --replace


Terminal Command:
gsettings set com.canonical.Unity.Panel systray-whitelist "['all']"