Add optional MS-based column comment["quantitation level"] for different TMT designs?

[jpfeuffer]

Hi, I would like to see an optional column that can be validated to specify quantitation level for different TMT designs like SPS. What do you think?

It can potentially be guessed when looking at the data, but it is a) clearer when this is specified, b) you can save some time checking the files and loading potentially unnecessary data.

[daichengxin]

It's a good idea, especially for TMT MS3 experiments. May need to add some ontology here: https://www.ebi.ac.uk/ols4/ontologies/ms/classes/http%253A%252F%252Fpurl.obolibrary.org%252Fobo%252FMS_1001833?lang=en