Note ipython dependency for dev.
Note ipython dependency for dev.

This is to regenerate examples.
[skip ci]

dopplershift/MetPy,deeplycloudy/MetPy,jrleeman/MetPy,Unidata/MetPy,dopplershift/MetPy,ShawnMurd/MetPy,ahaberlie/MetPy,jrleeman/MetPy,ahill818/MetPy,Unidata/MetPy,ahaberlie/MetPy