Update all package using MASTER_REPOSITORY_OPENROBOTS so that they now use
MASTER_REPOSITORY_OPENROBOTS_TRAC. This is to account for the upcoming
git.openrobots.org migration.

The MPC dem treatment is aimed at preprocessing the data elevation map
given by the DTM genom module to provide a representation of the
environment understandable by the navigation algorithms. It can compute
slope maps, classify the environment into free or obstacle, and compute
distance to obstacles maps.