xacro needed on BBB

[mangusman07]

i dont think its in instructions, the BBB needs to install ros-indigo-xacro in order to run.

[jasedit]

There are several packages which are not installed by default on the Beaglebone Black, which are required by this (and other) ROS packages to operate. Instructions should be updated appropriately, or someone should investigate why the run_depend defined in the khan_description package isn't properly being addressed by the ROS system.

[Mishra42]

This should be addressed in the branch I have out on my instructions upgrade. I'd love to get a newb to run through them for a dry run though.