implement plotting trait for reports and debugging purposes

trait that handles the plotting of specific light data with several possibilities, such as single line, multi-line, scatter, 2D, 3D (already partially written, but on an old ocal branch that is not compatible with current version).

Will be useful to test and debug the code.

Plotting to:

• images (png, svg, whatever)
• directly to a canvas (requires opening of windows and probably a GUI framework. however, may be useful when interactive zooming, rotation of the plot is implemnted)