Added sensors to the robot. Correct exit on sigint.

ant_bot.inc

@@ -1,3 +1,17 @@
+define ant_sensor sensor
+(
+	size [0.01 0.05 0.01 ] 
+	range [0 5.0]
+	fov 180
+	samples 180
+	color_rgba [ 0 1 0 0.2 ] 
+)
+
+define ant_sonars ranger
+(
+	ant_sensor( pose [ 0 0 0 0 ] )
+)
+
 define ant_bot position
 (
 	block
@@ -14,4 +28,6 @@ define ant_bot position
 
 	drive "diff"
 	localization "gps"
+
+	ant_sonars()
 )