[AstroPy] python equivalent to IDL routine smooth

[Joe Harrington]

Recall that in Fourier space everything wraps, so be sure to subtract
the mean and pad your data in a field of zeros large enough that your
kernel won't average data on the left edge with data from the right,
etc.  Then transform, multiply, transform back, trim, and add back the
mean.

There are some very nice wavelet-based smoothing methods, as well,
See paper by Torrence and Compo for painless introduction:

http://paos.colorado.edu/research/wavelets/software.html

I found the paper easier to learn from than the tutorial on the web
site.  No python code there but there are routines available in
Python.  Perhaps someone else has a suggestion on a good replacement
for the code on that page in Python.

--jh--