Use the LED to indicate boot and network status

## The first pass at this is boot status indicators of:

1. The bootstrap blinks `torch` once
2. There is no LED during firmware boot
3. Successful firmware init turns on `torch` then runs custom startup scripts
4. Successful custom-startup completion turns off `torch`
5. If battery alarm is on (<20%) and it is not charging, it then blinks `red` three times quickly
6. If custom startup changes the LED, no post-boot indicators are done

So:

* two torch blinks - full boot + power
* two torch blinks then three red blinks - full boot but low power
* one torch blink then off - bad firmware
* one torch blink then steady torch - good firmware but bad startup scripts

## The second pass is the mesh network status blink:

This is only enabled after `scout.indicate` is run (optional arg of number of seconds, 5 is default, 0 to disable).

* network status is indicated once every `indicate` seconds
* it blinks the `torch` color
* if any other scouts are detected the blink is very small (short)
* if no mesh/scouts are detected the blink is a continuous second (long)
* should restore any other LED settings after

## The third pass is the wifi status:

This is only enabled after `wifi.indicate` is run.

* when associating, it will blink green very fast
* after it associated and while it's trying to connect to hq it will be solid green
* once connected to hq it turns back off
* if it disconnects it starts over associating again