When FCL 0.6 is the default, bounding box code can be simplified

[AndyZe]

PR #210 had some #if - type stuff that can be simplified when the default FCL version is >0.5.

#if FCL_MAJOR_VERSION > 0 || FCL_MINOR_VERSION > 5
#include <fcl/geometry/shape/utility.h>
#endif

[peci1]

I suggested these simplifications in #239 for ROS 2. Noetic can probably be left with them.