Split ancientDNA sub-workflow into separate sub-workflows for running damage analysis and consensus correction

[alexhbnr]

Description of feature

Currently, enabling the ancientDNA workflow automatically enables the correction of the consensus sequence reported by the de novo assembler and the analysis of the presence of ancient DNA damage. The first step is mainly driven by the issue that we observed that MEGAHIT generates contig sequences that are riddled with nonsense mutations or stop codons when ancient DNA damage is present but were not supported by the short-read data.

When assembling with metaSPAdes, we do not observe such a behaviour and therefore the consensus correction might not be necessary. However, we still would like to run the evaluation of the amount of aDNA damage present using pyDamage.

It would be very helpful, if the two modules in this sub-workflow could be separated from each other, so they can be switched on and off separately.