Milkviz

- Add 3D scatter plot
- 2D scatter plot support specify a colormap for each unique type

- Better legends handling
- Better colors handling
- Parameters changes for some plots

1. 🔧 `milkviz.anno_clustermap` now supports drawing color legends column by column.
2. 👏 [New] `milkviz.stacked_bar` Add stacked bar plot.
3. 👏 [New] `milkviz.venn` Add Venn diagram, supports visualizing intersection between 2 or 3 sets.
4. 👏 [New] `milkviz.upset` Add upset plot, supports visualizing intersection between arbitrary sets.