Update to latest development version of openxc binary message format.
Update to nanopb v0.3.1.

Fixed https://github.com/openxc/vi-firmware/issues/269 but need to test
on hardware.
Ignore untracked files in submodules.
Merge branch 'next' into 269-latest-nanopb
Display all selection options when running 'make flash'.
Merge branch '269-latest-nanopb' into next
Update to the latest version of the chipKIT libraries.