Add testing mode for joystick reader.

Setting test mode on the DS puts it in a state where there are
buttons that individually move each subsystem up and down very
slowly. Useful when we are first bringing up the robot, to check
that everything works.

Change-Id: Ia2009d0478d3f6c9c7b44a03e7b7ca5955e9101d
3 files changed
tree: 171b5420767980112f6eccf47624a00654bbf70f
  1. aos/
  2. doc/
  3. frc971/
  4. output/
  5. vision/
  6. .clang-format
  7. .gitignore
  8. README.txt