Trajectory action should abort on robot error.

[hersh]

When a robot status message is received with a non-zero error code, any active trajectory goal should be aborted. Without this, the only way to know that a failure has happened is for the action client to time-out.

Also fixed some compiler warnings about printing unsigned integers with %d format.

[shaun-edwards]

@hersh, thanks for this contribution. I'm going to try it out on our hardware before I accept the PR. Should be a couple of days.

[gavanderhoorn]

I like this, but should the abort of the goal (and sending of the FollowJointTrajectoryResult) perhaps be done somewhere else instead of directly here in the RobotStatus callback? Maybe in controllerStateCB(..)?

[gavanderhoorn]

Also: perhaps we should actually check the in_error field, instead of error_code (or both)? I can imagine not all errors (on the industrial controller) immediately lead to an inability to complete the goal?

[gavanderhoorn]

Rebase + improvements in #271.

really late, but I'd still like to thank @hersh for making the effort to submit a PR.