Mention Snakemake wrappers

[tbooth]

from @cmeesters:

we recommend using Snakemake wrapper to handle awkward programs to increase the stability of workflows wherever possible. There is not even an outlook to wrappers. This is - IMO - a major flaw.

Snakemake wrappers are available for these tools:

https://snakemake-wrappers.readthedocs.io/en/stable/wrappers/fastqc.html https://snakemake-wrappers.readthedocs.io/en/stable/wrappers/kallisto.html https://snakemake-wrappers.readthedocs.io/en/stable/wrappers/salmon.html https://snakemake-wrappers.readthedocs.io/en/stable/wrappers/multiqc.html

But not for the older tools velvet or fastx_toolkit.