Create an easy way to add more cohorts to AnoExpress

[sanjaynagi]

To help future proof AnoExpress, it would be great to be able to add new transcriptomic datasets.

We have a notebook which combines cohorts. Lets make one which streamlines the process of adding a new cohort(s) to AnoExpress.

We will need to add:

• the read count data for each sample (gene-level)
• comparison metadata for each sample
• sample metadata for each sample

We need to run checks, checking number of genes, ensuring the metadata match up with each other, that there is not too much missing data etc.

Then we also need some documentation about how to run through this process.