Moved applets sources to dir services.
Makes more sense in imports when loading more than one.
Applet DiskSpeed: renamed to DiskActivity.
New command: cdc = cairo dock control.
    build       build a cairo-dock package
    install     install external applet
    list        list external applets
    restart     restart the dock or one or more applet
    service     start service with the dock or an applet

This gives a few helpers from command line, and the ability to start and handle multiple applets instances with control from Dbus.
Build option hasn't been retested yet, and will need a rework/merge with Update.