Add a `filter_with` method to `TimeSeries`

[mivade]

Right now, the way to do filtering goes something like this:

ts = TimeSeries(...)
filt = ButterworthFilter(...)
new_ts = filt.filter()

It would be nicer if we could use a method on the TimeSeries object itself to do filtering, something like:

new_ts = ts.filter_with(ButterworthFilter, **kwargs)