v0.3.0

Update compute_sister_cell_distance, also other minor updates

v0.2.0

Split the plotting api into two modules: tool and plotting, each each tool has its corresponding plotting function. The results are saved and attached at the anndata object.
Also split the large chunk of code into separate files if possible, to improve the code organization.

v0.1.9

Right after i finish 3rd round of review