make prompt '>>>' and output unselectable

[pdebuyl]

This is done by adding a custom css file that acts on the ".gp" and ".go" classes.

[GaelVaroquaux]

Is there a reason that you did not add this to our nature.css? The multiplicity of css files delays loading over http for users.

[pdebuyl]

As the nature.css file has a _t at the end and a copyright notice from the sphinx authors, it seemed as it was a "fixed copy" from somewhere else. I can include the modifications there.

[pdebuyl]

ok, 2 force pushes and that should do :-)

I can copy-paste from a few random locations into a terminal!

[GaelVaroquaux]

That's very cool! Merging.