From wiki, undocumented public functions

I'm tidying the wiki, this was a page out of place, moving to this issue.
Don't know what's the issue pd.to_pickle is certainly documented.
@JanSchulz?

Undocumented public functions

The following was found by http://nbviewer.ipython.org/urls/gist.github.com/JanSchulz/6874142/raw/fadef84066d89b3ceb7532e762ed06d87904f3c4/pandas_api.ipynb (and changing all context to pandas in api.rst)

[jankatins]

That was a doc for #5124 (merged)

I'm not sure how current this wiki page is anymore.

Thanks.