DUNE/Control/PathController: Time of arrival factor is now part of the General section in configuration. Getting value from params.
DUNE/Plans/SpeedModel: New member variable m_time_factor is the time of arrival factor.
DUNE/Plans/TimeProfile: Using time of arrival factor from SpeedModel.
Config: auv/general: Added time of arrival factor.
Merge remote-tracking branch 'origin/feature/time_factor'

Feature #3151: The factor used to compute the time of arrival to a
waypoint is now taken from the configuration parameter 'Time Of
Arrival Factor' of the section 'General'. This parameter has a default
value of 5.0 seconds for AUVs.

Authored by: Pedro Calado
Reviewed by: José Braga