Improve Display of Permissions on User Pages

### Current Behavior:
Dependency-Track displays that a user (Managed or LDAP) is a member of x teams.
When inspecting the user, DT displays "Team Membership" and "Permissions" as separate widgets, each of which allows Add/Remove functionality (eg, Add to Team & Remove from Team)


The challenge of working with this screen is that it provides no information on what permissions are derived from Team membership: one currently has to navigate to the "Teams" screen to see what Permissions are assigned to what Team, and to the Permissions screen o see what the Permssions actually do.

### Proposed Behavior:
* The Users screen would be enhanced by the addition of a listing of the Permissions that are derived from the configured Teams, with a column that names the Team/s (each Permission might derive from more than just one Team).
* The "Assign Team Membership" dialog should list Permissions for each Team.
* The "Assign Permission" dialog could be filtered to display those Permissions that are not currently assigned (this would become more useful as DT supports additional Permissions over and above the current count of 8 unique Permissions.
* Permission Description should be available in the above screen/dialogs