Add support for Graphite web aggregateWithWildcards function

[carrieedwards]

Is your feature request related to a problem? Please describe.
The aggregateWithWildcards() function is implemented in Graphite web, but is missing from CarbonAPI. In order to enable users to be able to use the aggregateWithWildcards() function, it needs to be implemented in CarbonAPI.

Describe the solution you'd like
The aggregateWithWildcards() function should be implemented in CarbonAPI, with the same functionality as the Graphite web function. The description of the function is as follows:

aggregateWithWildcards(seriesList, func, *positions)

Call aggregator after inserting wildcards at the given position(s).

Example:

&target=aggregateWithWildcards(host.cpu-[0-7].cpu-{user,system}.value, "sum", 1)
This would be the equivalent of

&target=sumSeries(host.cpu-[0-7].cpu-user.value)&target=sumSeries(host.cpu-[0-7].cpu-system.value)
or
&target=aggregate(host.cpu-[0-7].cpu-user.value,"sum")&target=aggregate(host.cpu-[0-7].cpu-system.value,"sum")
This function can be used with all aggregation functions supported by [aggregate](https://graphite.readthedocs.io/en/latest/functions.html#graphite.render.functions.aggregate): average, median, sum, min, max, diff, stddev, range & multiply.

This complements [groupByNodes](https://graphite.readthedocs.io/en/latest/functions.html#graphite.render.functions.groupByNodes) which takes a list of nodes that must match in each group.

Additional context
Tests should be added to verify that the functionality matches that of the Graphite web aggregateWithWildcards() function.