Adding optargs

[shdam]

Progress: banksy, drsc, maple, and meringue

What if a method takes both dimred and counts?

[Jieran-S]

The consensus from the last meeting was that if the configuration requires customized dimred, then we would input only raw counts. But if the methods only take vanila dimred such as PCA or other canonical methods provided in scanpy/osta pipeline, then we centralize the preprocessing steps and input only the dimred. Do these methods have any hard-code customized dimred methods? If so we can take raw counts, otherwise dimred input? :))