GridCluster class added , inheriting from PointSet

src/CMakeLists.txt

@@ -27,6 +27,7 @@ SET(HDRS
     corner_detector.h
     entities.h
     grid_2d.h
+    grid_cluster.h
     laser_scan.h
     line_detector.h
     line_finder.h
@@ -44,6 +45,7 @@ SET(SRCS
     corner_detector.cpp
     entities.cpp
     grid_2d.cpp
+    grid_cluster.cpp
     laser_scan.cpp
     line_detector.cpp
     line_finder.cpp