- The typical dboard classes are actually "subdev" classes i.e.
there is one instance per dboard subdev (front-end). This makes
it hard to implement shared functionality between multiple
front-ends.
- This changes adds the ability to create a container class which
is created per group of subdevs and each subdev gets a pointer
to the container class for cross linkage.
And created utility functions to go between representations.
Created to_pp_string for pretty print strings for dboard ids and device addrs.
Minor changes to the various classes that call these utilities.
