Update Parameter Declaration API to Include Direction so Default Bindings can be Automated

[liangfok]

Currently, default bindings are defined explicitly within a method called addDefaultBindings(). For example, see COMTask.cpp and JointPositionTask.cpp. I believe default bindings can be automatically done once the direction of the parameter is defined, i.e., is it an "input" parameter or an "output" parameter from ControlIt!'s perspective. Once the direction is specified, the user will only need to specify the transport type, which can default to ROS topics.