[feature] Loading Nested Dictionaries and handling lists of dictionaries
This is a repost of #9359 with some new fancy code that handles lots of different kinds of edge cases. Please take a look at the code:

https://gist.github.com/cloudformdesign/13278001b1a0b0cde647

Basically this allows automatic loading of nested dictionaries, whether those dictionaries are a "list of dictionaries" or a "dictionary of lists", it handles them as you would expect them to be handled by automatically creating a MultiIndex.

My hope is that the `dataframe_dict` function be used instead of the standard `DataFrame.from_dict` method. 

This is not an edge case -- this is a use case that arrives frequently for people who use mongo or who store data in nested dictionaries.

If you agree that it is functionality worth adding, I can make the changes to pandas and make a pull request.
