Add status indicator for users to quickly determine if the table is working

[uwekamper]

... for example some kind of blinken LED that blinks differently when:

• everything is okay
• network issues
• and so on ...

[brockhaus]

Perhaps issue #8 is a duplicate of this one..

[bergie]

Instead of a single light, why not just use all the lights we have available?

Though, usually the problem seems to be either in Node.js or communication with microcontrollers, and in these cases it is hard to deal with lights.

One potential solution would be to add a "dead man's switch" to the MicroFlo code that would do something with lights in case the microcontroller hasn't received anything from the RPi in couple of minutes. @jonnor how would one go about this?

[jonnor]

I think what makes sense here is to have in Flowhub using live-mode:

1. Indicator on how long ago since last info from Ingress API, plus last 5-10 messages received
2. A couple of triggers for test-data. Would send known, easily distinguisable info to microcontroller, for human visual verification