[refactor][lv-core] Enable All SLAM dependencies on CI

• Tested with every relevant combinations of {ENABLE_ceres, ENABLE_nanoflann, ENABLE_pcl} on Ubuntu20 (other platforms shouldnt behave differently)

Changelog:

• CI Enabled SLAM

• CI Enabled -DENABLE_ceres=True -DENABLE_nanoflann=True -DENABLE_pcl=True

• Reorganised LidarPlugin sources and tests by features, using cmake_dependent_option. Those are still enabled by default but new options enable allows to no build them.

• Renamed ENABLE_slam to feature-oriented/ non SB-conflicting LIDARVIEW_BUILD_SLAM in a paraview like convention.

• Reviewed some thirdparty dependencies (removed a PCL required here and there were only Ceres was needed)

• Retired OldSlam to TrajectoryReoptimization

• Deleted unused and empty LidarPlugin/Testing/TestCarGeometricCalibration.cxx

• Update relevant DOC

• Must be merged with sister branches AND SB RE-RUN

@jerome.dias @nick.laurenson