[BUG] When initialising a Dynamixel device the goal_position should be setup to the present_position

Describe the bug When the robot is initialised there is a risk of joints jolting suddenly depending on how the initial values are setup for goal_position, etc. To avoid this the goal_position should be set to the current_position before the torque is activated and any sync loop is started. At the moment the registers are initialised with 0 unless there is an explicit initialisation in the robot definition.

To Reproduce I've just broken the fingers of MH4 because the hand was moving so fast and in a trajectory so bad that is hit other parts of the robot.

Expected behavior When robot starts, it should be frozen in the initial position (before startup) and if any Scripts are run afterwards the position will be changed.

Screenshots N/A

Desktop (please complete the following information):

Board: [e.g. Raspberry Pi, Intel PC]
OS: [e.g. Ubuntu]
OS version: [e.g. 16.04 - Xenial]
Python: [e.g. 3.7]

Additional context

sonelu / roboglia

[BUG] When initialising a Dynamixel device the goal_position should be setup to the present_position #67