Add (some) support for rosparam

[adeguet1]

For data collection it would be nice to have a mechanism to retrieve all the configuration parameters used for the dVRK (IO, PID...) during the collection. One idea would be to have the dVRK console push the content of all the configuration files used to rosparam. This would not be a two way communication, at least in the first implementation (meaning that sendind a new parameter to rosparam would have no effect on the dVRK console).