ENH: Add option to display dtypes below column headers

[joaomacalos]

Is your feature request related to a problem?

My feature request is not related to a problem per se, but it can help users to spot type bugs and is not visually noisy.

I wish there could be a way to change the Pandas str and html representation to show the dtypes of columns below the headers (like R's tibble or Julia's DataFrame).

Describe the solution you'd like

I imagine that the solution would involve setting an option, e.g. pd.set_option("display_dtypes", True).

API breaking implications

As far as I understand, adding such option wouldn't break the API.

Describe alternatives you've considered

I could try to write something in this direction, but honestly I don't even know where to find the relevant source code to start. If someone could point me the direction I would be happy to try it out.