Support for TinyQED Wheel Encoder Counter

Added support for TinyQED Wheel Encoder Counters.
See https://github.com/renbotics/TQED
UPDATE: updated to be in line with original TQED function return value conventions (i.e. bool rather than void for resetCount()), and renaming back to TQED, rather than TQED2
Added PointCloud for Sonar
Pointcloud support for sonars

Added pointcloud support for sonar sensors (ping sensors).
This allows sonars to be used as "observation_source" in ROS's 2D costmap implementation (http://wiki.ros.org/costmap_2d?distro=groovy#Sensor_management_parameters).

The pointcloud is constructed as a 2D "arc" of the sonar beam.
Number of points that this arc consists off is determined by the MAX_SENSOR_POINTS value (hardcoded in arduino_sensors.py).