message: COMP: resolve ambiguous namespace with gcc6/gcc7
diff: #include <string> // for std::string
  #include <cstring> // for memcpy
  -// namespace aliases
  -namespace numerics = axom::numerics;
  namespace axom
  {
  namespace spin
  {
  +template < typename FloatType >
  +using floating_point_limits = axom::numerics::floating_point_limits<FloatType>;
  +
  //------------------------------------------------------------------------------
  // BVH IMPLEMENTATION
  //------------------------------------------------------------------------------
  @@ -257,7 +258,7 @@ IndexType bvh_get_raycounts( LeftPredicate&& leftCheck,
  template< int NDIMS, typename ExecSpace, typename FloatType >
  BVH< NDIMS, ExecSpace, FloatType >::BVH( const FloatType* boxes,
  IndexType numItems ) :
  - m_Tolernace( numerics::floating_point_limits< FloatType >::epsilon() ),
  + m_Tolernace( floating_point_limits<FloatType>::epsilon() ),
  m_scaleFactor( DEFAULT_SCALE_FACTOR ),
  m_numItems( numItems ),
  m_boxes( boxes )
  