Removed the transformation between laser and the child tf frame.
A static tf publisher is now needed to do this, wherefore slam.launch
now contains one.
Did some cosmetics (removed unnecessary dependencies, altered error
messages, removed couts and comments).
The minimum octave factor for the grid is set to 5 (values below
will result in strange SAGFAULTS). Even 5 will still result in a
ridicolously small representation size, but is the smallest value
not resulting in an instant SEGFAULT.
The robot footprint can now be set via launch file and is used to
clear a certain area in the tsdgrid during the initialization.
The initial push to the grid is now done by the main thread, hopefully
solving a race condition between first localization and first push
to the grid.