Please add Column Roles to AnnotationChart

[Rob Hannah]

It appears that AnnotationChart does not support roles. I am trying to attach annotations to the join table to better represent my data (instead of 'A', 'B', ...).

For example, assume I have a timeline of active publications. Along with that I have a series of events that are one of Submit, Review, Approve. What I would like to show for annotation labels would be 'S1', 'R1', 'S2', 'P1', 'R2', 'P2'...