added a plotting function for reduced dim

[jaspitzer]

I've added a plotting function for the reduced dimensions in tidybulk.
Type of reduction can be specified and respective column names are looked for. In case of PCA, the percentage of variance is reported.

I don't know if this is in the scope of the project at all or if users are supposed to plot themselves; I figured since it is fairly customary to report % of variance and there is no clean way to do this "in pipe", I build a function to do it. Pease let me know if this is something you'd want.

Also plan on implementing functions to produce some expression plots (and similar things) from specified transcripts, is that of interest?

[stemangiola]

Thanks @jaspitzer , this is probably the only plot that cannot be done with ggplot because of the % variation.

For the other plots, the concept of tidyverse is that using ggplot comes for free. Having said that, you could build wrappers using the current plotting standards showed in the vignettes. E.g. scale_y_xx utility we have for volcano plots.