Big rooms frontiers

[DmytroKushnirSoftserveinc]

When it happens that we obtain frontier which can be approximated with the line of lengths > 2 * r, where r is the lidar effective distance we face the problem when following to the center of it is generally a very poor idea: we cannot update the map, as orienteers are too far.

Proposed solution: Add heuristics which will give more value to the frontier segment in direct reachability of known landmarks.