Adjust legend of plot_rich_club

[KirstieJane]

The legend of the plot_network_measures function shows "Real Network" and "Random Network".

I think they make sense (although I'd probably not capitalise the "N") and so it would be great if the rich club plot could also have the same labels, and in the same order.

So switch the order and change text to "Real network" and "Random network" instead of "rich club coefficient" and "random rich club coefficient".

[wingedRuslan]

@KirstieJane, Sure, no problem. If I change the order in plotting_rich_club the grey line (random values) will be "on top" of the blue line (real values). This especially is notable at the start of lines (0 to 30 degree), when values are pretty much the same. Right now the blue "on top" cause we draw real network after random network, and that's why the order of legend is 1) random 2)real.

Is that fine?

[KirstieJane]

Heya - no - it isn't ok to put the blue line behind - the real data needs to stay on top. But check out this zorder demo to let you change the order of the plots 😸 🚀 https://matplotlib.org/gallery/misc/zorder_demo.html#sphx-glr-gallery-misc-zorder-demo-py

[wingedRuslan]

Addressed in #121