Support for loading 3D map as 2D and set new TOdomToMap

In addition to pullRequest for libpointmatcher in order to store 2D descriptors.
Modified `LoadMap` service to point out we want to load a 2D map.
Modified `LoadMap` service to point out we want to use an existing TOdomToMap.
Modified `mapper.cpp` to provide support to the new service and new debug function.