From: http://askubuntu.com/questions/35488/what-custom-launchers-and-unity-quicklists-are-available
Newer specs here: https://specifications.freedesktop.org/desktop-entry-spec/latest/apa.html
.desktop files stored in: ~/.local/share/applications
A. Example Desktop Entry File
[Desktop Entry]
Version=1.0
Type=Application
Name=Google Services
Comment=Quicklinks to all Google services!
TryExec=google-chrome
Exec=google-chrome https://google.com
Icon=google.png
MimeType=image/x-foo;
Actions=Gmail;Calendar;Voice
[Desktop Action Gmail]
Exec=google-chrome https://mail.google.com
Name=Gmail
Icon=gmail.png
[Desktop Action Calendar]
Exec=google-chrome https://calendar.google.com
Name=Calendar
Icon=calendar.png