fix doc typo
fix doc typo

thaddeustaylor/catkin,thaddeustaylor/catkin,harmishhk/catkin,wkentaro/catkin,asmodehn/catkin,beni55/catkin,wkentaro/catkin,jack-oquin/catkin,meyerj/catkin,harmishhk/catkin,ros/catkin,scpeters/catkin,jack-oquin/catkin,ros/catkin,shyamalschandra/catkin,beni55/catkin,beni55/catkin,asmodehn/catkin,scpeters/catkin,asmodehn/catkin,wkentaro/catkin,ros/catkin,thaddeustaylor/catkin,meyerj/catkin,shyamalschandra/catkin,jack-oquin/catkin,meyerj/catkin,scpeters/catkin,harmishhk/catkin,shyamalschandra/catkin