I have been asked this information multiple times now, and I did some calculations for the research paper we're writing. So I think it's useful and nice to add a proper table about the computational performances of the package. We still have to decide what we want to include and how, but we can take inspiration from the old deeprank paper (see Supplementary Table 3), which contains a computational performances table.

Add a reference to it also in the JOSS paper (PR #423)