Added hist method and added auto_x argument to plot method.

[ghost]

I have added hist method to frame.py and series.py, and added auto_x argument to plot method, which can be useful for the cases where the index does not consist of numeric values.

-Joon

[wesm]

Hey there-- I just made a commit to my branch with some modifications to your changes.

I tried to merge your branch but there were some gnarly conflicts so I just decided to do it by hand-- I named the "auto_x" parameter to "use_index", so it has a similar effect. In the future could you make sure to merge the upstream changes before making changes? =) That will help avoid merge conflicts on down the road.

wesm@2db763f

Thanks for your help,
Wes

[ghost]

Will do and I'm sorry about the confliction!