ciaranj/chartled — pull request #7 by sheltonash (2014-03-14 12:24:45+00:00)
Title: Add support for the diffSeries function

The diffSeries function subtracts metrics, lists of metrics and
constant values (parameters 2 through n) from parameter 1 - which
in turn is fleixible and could be a metric, list of metrics or a
constant value. Order of parameters 2 through n is not important.
Where as parameter 1 provides the initial value or list of values
to subtract from

Examples of usage:

diffSeries(5, foo.bar);
diffSeries(foo.*, 2, meep.bar);
diffSeries(*.*);