Feature Request: Simplify and automate `generate_sdtm_supp` use

[billdenney]

Feature Idea

I think that it would help if generate_sdtm_supp() were able to generate the SDTM with fewer instructions (i.e. arguments). Some ideas include:

• Domain detection can occur because each domain should have a DOMAIN column.
• For each domain, auto-selection of the idvar could occur and be verified that it was unique.
• The supp_qual_info could be auto-generated from the source data.frame itself as long as the column had a label based on ordering with the column order of columns that are not in the required, expected, or permitted set. (That would also remove the requirement for qnam_var, label_var, and orig_var.)

Would this be of interest?