Fix missing 'self' argument in some geomaps functions
Dist is now a function of Geomap object
Add a travel cost function for the robot, used to compute the path links
glpk solver is now a class (not a stand alone function)
Add a penalty for large plan cost
The maximal cost by perido is defined by the mission file (json)
Fix mission caylus (period, start poses)
Fix mission empty_space (period)
Fix mission manhattan (period, start poses)
Fix missing self in geomaps
Fix distance in geomaps (scale)
GLPK_Solver: plan_cost is now really take into account as a secondary objective
Display sampled robot positions when not path links
Add a catalog of sensing functions for robots
Utility is not faken anymore: use map and sensing
Geomap: add function to navigate between pix and meters unit.

length_pix2meter
length_meter2pix

While here, clean up and fix distance (respects the length unit)
Use the new meter2ix functions for cost computation and display
Fix utility computation
Lower cost penalty magic number
GLPK solver output extra data