Add numpy array support to tabular_data

[dnmiller]

It would be nice to have support for instances of numpy.ndarray instead of having to rely on pandas.DataFrame. This would extend vincent to work with some non-statistical applications, like simulations or stuff imported from Matlab.

I've got a branch in the works for this, so I'm just throwing this issue out there for comments. It's coming along well, but I'm not sure when it'll be finished, so not sure if it should go in v1 or not.

I'd like to see vincent get to the point where it's a viable replacement for matplotlib. I think it would get surprisingly close to reproducing most of the functionality with this change.

[wrobstory]

Sounds great- just keep plugging away, and don't worry about timeline. I've actually been thinking that it's probably best to move the dev status to Beta as soon as the docs get built, and keep iterating from there. Pandas is widely used, and they still consider themselves beta.

I think for Vincent to be a viable replacement, it needs to be easy for people to save PNGs without taking a screen grab of their browser or dealing with localhost. I've been thinking about talking to nodejitsu about hosting a very simple app running Vega in headless mode, so that people can do something like vis.to_png(path), and it will execute a POST request to the server for the PNG.