DO NOT MERGE update to the new driver API and move to subclassing iodrivers_base::Task

This benefits from the changes in the driver (rock-drivers/drivers-sonar_tritech#1) to simplify the task as well. Moreover, this makes it easy to integrate within the iodrivers_base::Task framework, and so updates the code to subclass it.
How do you would like to handle such information in the future?