suggestion on color options

[mortunco]

Hi,

Thank you for the tool. My PI loves venn diagrams and it was very painful to draw them manually.

I have couple minor suggestions.

1. I tried to get one of the known sets (ex: Set1) but current form of the tool only accepts spesific colors rather than the defined colormaps. Implementing this could be useful.
   https://matplotlib.org/3.1.0/gallery/color/colormap_reference.html#sphx-glr-gallery-color-colormap-reference-py

2. Labels of the plots should be independent from the venns color or maybe in default it is the same color as venn color. However, i would like to make the label just black.

I can give this a try if you guys are busy.

Cheers,

T.