flatten, multiIndex, agg, groupby
Maybe this is even simpler, but how does one turn a  MultiIndex back into a bunch of columns?  

```
aaa = subby.groupby(['fxVersion','operatingSystem','updateChannel'])['isCompatible'].agg(dict(sum=np.sum,pct=lambda x: 100*np.mean(x),count=lambda x: len(x)))
```

So far, this is the best I have:

```
pandas.DataFrame(map(list,aaa.index.get_tuple_index()),columns=aaa.index.names)
```

Maybe it is just me, but I just don't get what MultiIndex is trying to do :)   I have them after groupby().agg.  When `as_level=False` is on, some types of `agg` don't work.  Something here doesn't quite gel for me!
