Adding blinking LEDs to config mode

[scottjenson]

trafficstars

This just cleans up the LED blinking code a bit, expanding the original blinky() function to a few more helper funcitons. This cleans up app_start a bit and sets us up to make the config.json file turn on/off the button and LED functions. This current version is very specific to the current Google MinewTech beacon. We need to move to more modular code to turn off big sections. Note there is no significant functional addition w/ this change, it is simply a code clean up

[ciarmcom]

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[scottjenson]

First pull request. Not clear what the process is. How would you like me to verify?