Remove pmperson module in D8

I want to propose for discussion that we remove the pmperson module from Drupal PM when we port to Drupal 8.

This module used to contain quite a bit of functionality, but since we moved to using user accounts rather than a person node type, the module now simply adds a few fields to the user profile. I'm not denying these fields could be useful to some, but given how easy these are to create through field ui, I don't think it makes sense for us to be keeping the module just for them.