User Roles UI lacks ability to categorize roles

The RBAC roles api returns (at most):

"role": " "

"bucket_name": " "

"name": " "

"desc": " "

"ce": true

To categorize roles into admin vs. data roles (extremely useful to simplify the UX of assigning roles and editing users' assigned roles), we should add two fields called something like “ui_cat”:"" & “ui_order”:""

https://docs.google.com/document/d/1a8FyCsYC5rdarvDtUUb_fQwgbWRbQyisLkm8_LwKIyw/edit?usp=sharing