Bring IAM principals page up to par with policy pages

[sethsec]

Specifically it would be really great to have the following UI features on the IAM principals page:

• Expand/Collapse all
• Sortable table the top summarizing the IAM principals data

Generally, make it easier to find and/or filter just the roles that are vulnerable to one class of attack (privesc, resource modification, etc.).

[kmcquade]

This definitely would be a welcome improvement, I agree :)