Topics over "/p3at" namespace

[adrianohrl]

All p3at related topics should be over "/p3at" namespace according to [http://wiki.ros.org/Names](resource names) and [http://wiki.ros.org/ROS/Patterns/Conventions#Topics_.2BAC8_services](topics and services conventions). Only /odom and /cmd_vel are over "/p3at" namespace. The following topics should also be over it: "/scan*", "/gps*", "/imu*", "/coils", etc.; that is, all topic that are not related to the judge or the minefield viewer.