Disable downloading of packages.

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    Devices: deb, flo, fugu, grouper, tilaplia, flounder, mako, shamu, and manta
    Apps: Browser, Calender, Launcher2, Music, and VoiceDialer
    Wallpapers: Galaxy4, HoloSpiral, LivePicker, MagicSmoke, MusicVisualization, NoiseField, and Phasebeam
    Darwin prebuilts