Fork from https://github.com/ros-planning/navigation/tree/melodic-devel/amcl with some changes.
- The name of the map topic can be changed via reconfiguration
- Fixed uninitialized frame names becoming valid after the tf_prefix is removed
- Avoid that a negative covariance is stored to the parameter, to avoid not-a-number issues at map-updates
- Possibility to change the scan-topic dynamically
- Added possibility to ignore beams during calculating probability for the given pose
- Avoid that the amcl node writes its last pose to the parameter server