Settings: Upgrade network traffic meter (2/2)

    based on Omni, LiquidSmooth commits
    add custom icon mask color also

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    *Updated class name to be less ambiguous
    *Replaced the multi-check in settings with a proper listview
    *Added the ability to view up-stream, down-stream or both
    *Added the option to change how often it refreshes
    *Added a check before it updates the status bar to prevent it from
    refreshing everything needlessly
    *Added icons to show data direction
    *Remove unused style attributes

    Icon artwork is courtesy android design downloads