Biological deamidation special cases

[acesnik]

Right now, we require the observation of a proteoform without deamidation to call an identification of one with deamidation, since it is a frequent sample preparation artifact.

There might be interesting deamidations, though, and if we're interested in those in the future, we should consider some special cases.

Namely, if we have UniProt-annotated biological deamidations, we could consider those as possible identifications without identifying the unmodified form. However, we'll need to do more to differentiate the deamidations from GPTMD (possibly from sample artifacts) from the UniProt-annotated ones.