nucleotides ballons don't obey preferences for residue id

[Greg Couch]

ChimeraX dynamically changes how the residue name appears based on the number of open structures and whether or not it should show the atomspec. Nucleotides bakes in the atomspec version because it adds in what part of the nucleotide it is rather than all of the atoms. The solution includes using str(residue) instead of residue.atomspec() and delaying the call.