[Monitoring] Only elevated permission users should see Setup Mode

[chrisronline]

Right now, all monitoring users are able to enter Setup Mode, but this should be restricted.

Currently, the basic monitoring user will run into errors with the following permissions:

• cluster:monitor/state
• indices:monitor/settings/get
• cluster:monitor/nodes/info

We need to figure out a way to detect these privileges for the current user and enable/disable the setup mode UI accordingly.

[elasticmachine]

Pinging @elastic/stack-monitoring (Team:Monitoring)

[chrisronline]

This permission set would work for Setup Mode

[chrisronline]

Another note here.

@jasontedor recommended migrating away from _cat/indices (all _cat apis in general too) and try something like _all as a way to get the list of indices, as used by this call