Create phosphor-gpio-util framework

This application can write GPIOs.  Read support may
be added in the future.

Aside from just setting a GPIO low or high, it can
also do: 0 -> <delay> -> 1 or 1 -> <delay> -> 0.
All functionality will be added in future commits

Change-Id: I2d3c761eb909ddce3952bfb3173ce271f03544ba
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
5 files changed