[JdeRobot] Help choosing most convenient fix for warning about sscanf string format

[Oscar Garcia]

Hi again,

There is another warning that I'm trying to fix in drawarea.cpp from 
rgbdViewer and rgbdManualCalibrator components.

This is the issue at github: 
https://github.com/RoboticsURJC/JdeRobot/issues/17

Again, I can't test if because I don't have rgbd cameras, so I need help 
to know why this warning was not solved before and decide between 
removing excess "%s" or give sscanf a new parameter defining a extra 
element in words array.

After fixing that last issue the compile chain for jderobot will be free 
of warning messages.

Thanks.