Add alternative labels where needed

[ramonawalls]

Using design patterns creates PPO term labels that reuse the label from the input classes. For example, PPO_0002346 will be labeled "strobilus present" instead of "cones absent". We should create alternative labels that use the alternative structure from the PO as well as structure labels familiar to our users.

[ramonawalls]

@jdeck88 please follow this issue as well.