v2 Added option for padding.
Updated:
upper(src, padding) Produces the recent local upper limit for a given series.
Parameters:
src: The source series to derive from.
padding: Gives some extra room when lowering the level.
lower(src, padding) Produces the recent local lower limit for a given series.
Parameters:
src: The source series to derive from.
padding: Gives some extra room when raising the level.