Added a link to the new preinstalled packages list

Author: gmfricke

README.md

@@ -41,6 +41,8 @@ rosdep update      # Note this is not run with sudo
 
 Note: if you accidentally ran ```sudo rosdep update``` you can repair the permissions ```sudo rosdep fix-permissions```.
 
+You may request the installation of addition packages on the competition rovers. To do so create a pull request modifying the [preinstalled packages list](https://github.com/BCLab-UNM/Swarmathon-Docs/blob/master/PreinstalledCompetitionPackages.md) document.
+
 ##### 2. Install additional ROS packages
 
 We use the [catkin_tools](https://catkin-tools.readthedocs.io/) package to build the Swarmathon-ROS code base: