In the Command Center Dashboard, show the live Green/Red status for each firefighter in the current event

_"As a Command Center leader, I need to see the live status (Green or Red) for each firefighter in the current event, so that I can determine when it's appropriate to remove them."_

This is the main web application home Screen for the Control Center leader

* One Green icon for each firefighter connected to this event
* Icon goes red Red when any sensor crosses a safety threshold value (yellow will come later as a warning/prediction that they're likely to cross that value in within the next X minutes). How long should it stay red after the sensor value falls back underneath the threshold?
* The 'red' threshold values for each sensor must be configurable from the start (as part of this story), they will not be 'prescribed' by IBM or Prometeo. A dev-file based configuration is OK, there's no need for configuration screens. Note: it's also likely that the web server will need to send these threshold values to the IOT device in a future production-hardening story (for offline / outage behaviour)

Questions / Issues / Concerns:
* For now, we'll work from the draft image below. However, there's a lot to be considered in the design of this app.
* What does the Control Center leader need to see? Is it just the Green / Red status here and then they can look more deeply in the event a FF goes 'red' ? Do they need to see a firefighter's cumulative exposure over most recent (say) 10 mins? Does it differ from sensor to sensor? (e.g. do they care about Temperature as it is _right now_ but for NO2 it's the exposure in the last 10 mins?)
* Presume they need to know if the information is up to date or stale
* Do they need to see the live readings at all, will that be meaningful (or more meaningful for some things like temp than for others like NO2 ppm)?
* How frequently should the information be updated - seconds / minutes?
* What to show if information is >N mins stale?
* What to show when device / Phone link stops working? (note: firefighter may not be able to access the phone to correct this)
* How much information is too little / enough / too much. What's the right ‘cognitive load’ for the Command Center leader?

**Current Design Draft [may change]**