Warnings when build -reference only

[Tjaart-Hobby]

Hi
Maybe you would like to know about warnings I get when building. Rviz does not respond to cmd_vel inputs. Not that it matters the driver for hoverboard works.

[Tjaart-Hobby]

Sadly these build errors/warnings causes the rgb images not to be time stamped. They can't be used in depth mappings like Rabmap.