Use SteadyTime and SteadyTimer for bond timeouts

[flixr]

Fixes #16

Depends on ros/roscpp_core#57 and ros/ros_comm#1014

Tested and working on Ubuntu14.04/Indigo.

[wjwwood]

These changes lgtm, but it might require that this repository create a new branch for lunar, if the upstream API addition only gets merged there. It would need to be backported to all supported ROS distributions to avoid any branching in this repository.

It would also be possible to use the preprocessor to conditionally use SteadyTimer when it's available from roscpp, but that's up to @mikaelarguedas.

[mikaelarguedas]

@flixr I merged some cosmetics fixups on master so I took the liberty of rebasing this branch.
It looks good so far, I have some more testing to do though.
I think the fix is critical enough to be made available for every ros distribution. I'll wait to know if SteadyTimer will be backported for all active ros distros and make the appropriate changes based on this information.

Thanks for providing a fix for this! That's a bug that has certainly been impacting many users

[mikaelarguedas]

LGTM, waiting on approval on ros/ros_comm#1014 and ros/roscpp_core#57 to decide if this can me merged as is or need a distro specific segregation (preprocessor or branching out)

[mikaelarguedas]

@mikaelarguedas to either branch out or ifdef to use the new timer only on Lunar

[mikaelarguedas]

ros/ros_comm#1014 and ros/roscpp_core#57 have been merged so I'm going to merge this for lunar. thanks @flixr for the valuable contribution, that's a great improvement!