Development

See merge request !1

Solved a bug in the get_prev_segment() function: the next lanes references where used instead of the previous ones.

Added functions to get the left and right lanes.
Added functions to get the left and right road marks.

Merge branch 'master' of ssh://gitlab.iri.upc.edu:2202/mobile_robotics/autonomous_driving/autonomous_driving_tools

Added images needed by the documentation.